prince. the name sake he never got to meet. >> that's all for this edition of dateline extra. i'm craig melvin. thank you for watching. i'm really sorry. i understand why they hate me. i live with those same feelings about myself every day. to anyone that's -- for the role i played, i'm deeply, deeply sorry. it was right out of a soap opera. the husband, the wife, the affair with the local dentist. >> blew me away. like wow. he could pull me in so easily. >> but the script turned dark when her husband turned up dead. >> everything was a blur. she just said they found him in his car outside his gym. >> a simple tragedy. >> we all assumed it was a health-related death. >> heart attack, aneurysm. >> police dug deeper. >> 40-year-old men don't just drop dead. >> they believed it was a poisoning.

>> someone else was there with him that morning. >> this is now a murder investigation. >> 100%. >> the wife? >> she was on our radar. >> i had nothing to do. >> her lover? >> i knew he was innocent. >> this small town is full of secrets. his murder, one of them. >> you're hearing about a love triangle and poisoning, death. >> oh, my god, this can't be happening. >> i'm lester holt and this is "dateline." here's andrea canning with good husband. reporter: a new love makes the world seem a little brighter. >> he had a very smooth, i wanna say, almost sexy way about him. >> reporter: makes the heart beat a little faster. >> reporter: was it passionate? >> yeah. >> reporter: but when that love is forbidden. >> i was, like, "what? how can that be? how could i not have known?" >> reporter: a family would wonder if other secrets might be hidden. >> "why would you do this?" "how could you be so

irresponsible?" >> the whole thing was an atrocity. it wasn't a tragedy. it was an atrocity. >> reporter: it all began just a couple of hours north of new york city. a photographer's dream called the hudson valley. rolling hills. a majestic river. and quaint small towns. for linda kolman, it was the perfect place to raise a family. >> i grew up in saugerties. small schools, you know. just involved in sports and things like that. >> reporter: everyone seems friendly and it just seems kind of -- >> yeah, they're small-home towns, you know? >> reporter: it's where linda lived with her husband tom and their family. a loving home where they celebrated birthdays and holidays. thanksgiving 2011 was a busy time, visiting relatives, over-eating, and watching football.

>> he just loved the game of football. and he was a giants fan from a kid. >> reporter: and you took him to his first giants game. >> i did. i have pictures of him, like, you know, standin' down by the field like, "look at me." >> reporter: kid in a candy store? >> yeah, yeah. it was great. >> reporter: both linda and tom had been married before, but this felt like the real deal. >> reporter: what was it about tom's personality that made him so lovable and made you love him? >> he had a shyness about him that was sweet. he had like a -- like a kinda shy, flirty kinda way. it was just adorable. >> reporter: when it came time to tie the knot they rolled the dice and eloped. >> reporter: little white chapel? >> a chapel in bally's. yup. it was beautiful. flowers, music. really beautiful. >> well, it was unusual, you know, walking through a casino and someone's got a wedding gown on. >> reporter: the only guests

were linda's parents and tom's mom and dad, marie and tom senior. >> reporter: did you feel touched that they had asked you to join in this special occasion? >> absolutely. >> reporter: did they seem like a good match? >> i think they fit, yeah. >> reporter: both tom and linda had kids from their previous marriages. but a few years later, they welcomed a child of their own, ryan. >> he would say all along through the pregnancy, "i don't care if the girl or boy, i'll love it either way." you know, but i kinda knew deep down he wanted a boy. and so when he was delivered and he saw it was a boy, he cried. he was so happy. really happy. >> reporter: did you immediately see a relationship made in giants heaven after that? >> oh absolutely. >> reporter: they were a blended family his, mine and ours as they liked to call it. linda had a daughter who lived with her and tom. while, tom's two kids from his first marriage lived in colorado, brad and daughter jillian. >> i grew up knowing that my step-siblings were my siblings. it never felt not normal, you know? it felt like at dad's house, that was my house.

>> reporter: and despite the distance, tom was very close to his oldest kids. >> i was a daddy's girl, definitely, no doubt about that he always made sure that whenever brad and i were in town that we would have fun. like we -- we wouldn't just, you know, be sitting around. we always had fun plans. >> reporter: jillian and her dad talked on the phone all the time. thanksgiving weekend 2011 was no exception. >> and i remember we hung up and we blew a kiss over the phone like we used to when i was ten and we hadn't in years and i thought that was cute. >> reporter: and when the weekend of family and football was over, it was monday, november 28th. and lucky for tom, the new york giants were on t-v. >> he stayed up and watched the football game, a giants football game. i went to bed. >> reporter: the next morning, as usual, he was up and out of the house before linda and the kids were even awake. >> he normally got up to go to

the gym, around 5:30 and gimme a kiss on the forehead. >> reporter: after working out, like clockwork, he always went straight to his job as a physical therapy supervisor. he and linda usually texted soon after. but when linda sent him a message that morning -- >> i didn't get a response. and normally, tom's very good at responding. i was gettin' a little concerned. but, you know, maybe he's in a meeting, maybe he's, you know, whatever, he's tied up. >> reporter: she wasn't really worried until her phone rang. it was a friend of tom's named gil. >> i got a phone call from gil saying "have you heard from tom?" and i said, "no. have you heard from tom?" and he said, "no, but he didn't show up at work. >> reporter: what's going through your mind? is there concern or just, oh, maybe he's at the gym? >> tom would never miss a morning of work. >> reporter: linda jumped in her car to to retrace her husband's steps, hoping to find him. she never imagined that search would lead where it did. when we come back, linda's heartbreaking discovery.

>> i saw his car. i was like oh, my god. >> he had gone to gym. in fact, he was still there. >> i'm like wake up. what are you doing? they're looking for you at work. i was like oh, my god, this can't be happening now. with this one little nexgard chew comes the confidence, you're doing what's right, to protect your dog from fleas and ticks for a full month. it's the #1 vet recommended protection. and it's safe for puppies. nexgard. what one little chew can do. so you have ten years experience... i do. but no phd? i do have a masters in early childhood development. you don't mind if i record this, do you? uhh, no! first kid here's all the numbers, food's in the fridge, oh and lucas likes to pull on jewelry so you might want to lose the nose ring. by their second kid, parents are more likely to choose luvs. it absorbs 20x its weight and the new triple leakguards lock away wetness for outstanding leakage protection.

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zzzquil pure zzzs. naturally superior sleep. >> reporter: tom kolman wasn't the kind of guy who didn't return calls from his wife and he always showed up for work. his family says he loved his job as a physical therapist. >> he was always dedicated to, you know, his work. and he loved it so much, he went to get his doctorate in physical therapy. >> was he the type of person who liked helping people? >> he did. elderly people just loved him. he was such a sweetheart. >> reporter: so that morning when tom went m-i-a, linda was frantic as she jumped in her car to look for him. >> he usually goes to the gym and then to work. so -- i went to the gym. >> and i pulled in and at first i didn't see his car. but then as i pulled further through, i saw his car. >> i just pulled up alongside and i looked over. and i was, like, "oh my god." he was layin' down. >> and i thought, "he fell

asleep. like, he looks like he's sleepin'." and -- so i jumped outta the car and i opened the door and i jumped in. and i was, like, "wake up. what are you doing? they're lookin' for you at work --" >> reporter: but tom wouldn't wake up. linda called 9-1-1. >> ulster 911, what's the address of your emergency? >> i'm in. i'm in the parking lot by planet fitness in kingston. i was looking my husband and found him in his car. and i don't know if he's breathing. >> what did you think had happened to him? >> at that point, maybe he had a migraine and took some migraine medicine and laid down. >> but he's not waking up while you're waiting for the ambulance, no matter what you're doing. >> his hands were really, really cold. and then i realized that his nails were blue. >> you've got to send somebody. >> ma'am. are you able to check and see if his chest is going up and down? >> i don't think it is. >> reporter: paramedic, tim mitzel, was one of the first responders. >> i believe we were here within about three minutes of the call. >> what did you see, as soon as

you arrived here in the parking lot? >> mr. kolman's car was parked here. and mrs. kolman's car was parked here. mrs. kolman was on the side. she was very distraught. >> did you attempt to resuscitate him -- >> we did not. >> after my ex -- quick examination, i could tell that there was nothing that -- nothing that we could do. he had been deceased for a while. >> the paramedics, they just stood there. and i was, like, "what are you doin'? like, help him. just get in the car and help him." like, and they just stood there. they were, like, "no." and i was -- i just was, like, shocked, like, can you just try, you know the one just said, "no, he-- he's gone." and he did, he just felt so cold. >> did you just feel like this is so unfair? >> yeah, i just -- i just was, like, "oh my god, this can't be happenin' now. you can't leave us now." >> reporter: shortly after tom's friend, gil, called linda, and rushed to the scene. that's him in this dashcam video -- off to the right, collapsing

in grief as he learns the news. meanwhile, first responders and arriving officers processed the scene. >> anything unusual about his body? or did he just look peaceful? >> his trousers were open h -- just a little bit. his collar was undone. his shirt was kinda pulled out. and he was reclined back in his car. and i felt like he -- it looked like he took a nap and didn't wake up. there was a little presumption that it may have been a heart attack or, you know, cardiac event, or something had happened. he was a large man. >> reporter: but since tom's death was what police call an 'unattended death', there had to be an investigation. detective mike thomas and lieutenant kyle berardi both worked the case for the ulster police department. they took note, of how linda, the wife, was reacting at the scene. >> her demeanor, was it exactly what you would expect from a wife making a discovery like this? >> 100%. 100%. there was nothing out of the ordinary with her -- reaction,

her words. it was more hysteria. >> reporter: police escorted linda down to the station to ask her questions about tom's health. >> she had mentioned to us that he had hypertension. he had -- sleep apnea, which if you're not familiar with sleep apnea, unfortunately, they ultimately stop breathing at certain times during the night. >> that sounds dangerous. >> absolutely. he was diagnosed by his doctor as having a severe case of sleep apnea. >> did you, kind of, think that this was g -- going to be an open and shut case once you got the autopsy results? >> yeah. absolutely. and -- and that unfortunately was not -- not the outcome the next day. >> reporter: instead, the results would turn this tragedy into a tangled mystery. coming up -- >> 40-year-old men don't drop dead like that. >> a blockbuster new clue. >> what did that video show?

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>> reporter: just after a busy thanksgiving weekend, linda kolman found herself surrounded by family and friends again. this time it was not to celebrate, but to grieve. tom, her husband of ten years, was dead. >> think she was just in such a state of shock that it's almost like she wasn't there. >> reporter: linda's sister, debra, raced to saugerties. >> my family were there -- my parents. and -- there were some friends. i had gathered some of the close friends. >> reporter: there were so many people to tell -- tom's siblings broke the news to his parents. >> when i came home at 3:00, all

my children were at my house. they were told, which was that it looked like a cardiac event and he didn't survive it. but -- we just couldn't believe it. >> why didn't you believe it? >> well, he was always in good shape, exercised and everything. all right, he's a little overweight. but still, he tried to, you know, he was -- he was healthy. >> reporter: his daughter jillian and son brad, found out from their mom, michele - tom's ex-wife. >> she just looked at both of us and no beating around the bush, just said, "your dad is dead." and i just-- everything was a blur. i mean, words like, "heart attack," and, "aneurism," kept flying at me and none of it was

registering. it was just utter heartbreak. >> the three of us stood together hugging and then collapsed onto the floor. but it did seem to be a really long time that we just didn't let go of each other. >> reporter: they flew to new york and joined the growing crowd at tom and linda's house. >> linda was a wreck. she needed help standing up sometimes. she was just riddled with grief. >> you have time to even grieve >> reporter: as the kolmans made funeral arrangements, investigators met with the medical examiner to nail down the cause of tom's death. what they heard changed everything. >> it was undetermined pending toxicology results. >> reporter: the medical examiner explained there was no evidence of a heart attack, aneurysm, or any health related event. >> you got an undetermined cause of death on a 40-year-old male, which 40-year-old men don't -- just don't drop dead like that. >> are you still thinking that this could be medical or are you starting to think, "we could have a homicide on our hands"? >> you can think both at that point in time because we've had -- had to wait for toxicology reports to come back to -- to

come up with a cause of death. but in the meantime, we're -- we're thinking -- i would say thinking the worst. until we can disprove that it's not a homicide, we've got to treat it as such. >> reporter: crime scene techs worked on tom's car and took swabs for clues. while detectives set out to learn more about his movements on the day he died. linda told police the last time she saw tom was the night before, watching football. she assumed he left for the gym the following morning around 5:30, so investigators pulled security video of the parking lot to see what that could tell them. it was dark and grainy but revealed a lot. >> in the video itself we were able to observe a white suv -- arrive in the parking lot of planet fitness and that was about 4:30 in the morning. ten minutes later we actually see thomas kolman's vehicle pull into the parking lot and park right next to this white suv. >> that's when we knew that

obviously someone else was there with him that morning. >> the plot really thickened, i'm sure, after seeing that video. >> yes. >> so this is the planet fitness right here? >> this is planet fitness to your right. this is -- >> where -- >> where tom worked out every morning. >> i'll pull into tom's spot. >> reporter: bill weishaupt is a retired f-b-i agent and the chief investigator for the ulster county district attorney. he showed us in the light of day what's hard to see in that grainy video. >> this is exactly where tom was parked, right here. which is-- as you can see, it's a great distance away from the planet fitness where he normally worked out. and so this would not be a normal parking spot to pull into at that hour in the morning to work out in that gym. >> and the mystery suv pulled up where? >> mystery suv pulled up right here. so they were both facing -- which is -- this is north. >> could you identify a person, a make, a model of the car? what details were you getting? >> no, it was pitch black. these lights were not providing any illumination at all. the only thing we could observe was that the two vehicles were parked side by side for about 30-35 minutes.

>> reporter: the mystery s-u-v left around 5:30am. but tom's car never moved. >> what does that tell you? >> there had to be contact between the two to meet at this point, at that hour. so we knew now that someone had met with him prior to his death. and we now have to figure out who that is. >> reporter: easier said than done, of course. >> we just pulled up here. and lo and behold, there was a white suv here beside us. there is a white suv there. there is a white suv there. once you think about it, there's a lot of white suvs. they're everywhere. >> they're everywhere. >> reporter: but thanks to the video, investigators now thought they had an important lead to help narrow their search. >> whoever tom was interacting with in this white suv, he was expecting him. and he -- he knew him. >> reporter: time for investigators to start looking at tom's inner circle. picking apart his simple suburban life. >> linda kolman, i would imagine, would be someone that you would wanna look closely at.

>> no question. if there's a death that is not a natural death, you look at the closest -- people first, usually the spouse. coming up -- >> he did want to talk to me. >> soon they discover another reason to take a look at linda kolman. >> we had a relationship. >> sexual relationship? >> he's having an affair with linda koleman. >> it caught us off guard. of 1 2 3 medicines with trelegy. the only fda-approved 3-in-1 copd treatment. ♪ trelegy. the power of 1-2-3. ♪ trelegy 1-2-3 trelegy. with trelegy and the power of 1 2 3, i'm breathing better. trelegy works 3 ways to open airways, keep them open and reduce inflammation

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>> reporter: with no obvious medical explanation for tom kolman's death, ulster police decided to treat it as a possible homicide, but said nothing to his family. >> we just had to just s -- sit back and wait till -- we found out a cause of death. and that's what we did. we just sat back. >> reporter: for tom's parents, burying their first-born was excruciating. but something the funeral director said gave them comfort. >> "when -- people c -- die, and if they're well respected, people come from all over." >> and they did. i had relatives from rochester, long island, new jersey, virginia -- even from california.

>> how moved were you at the funeral as you heard people speak about tom and all the love that was in that room? >> just cryin' all the time. >> walking into the wake was probably one of the hardest things i've ever done. i -- i waited for all my siblings and all four of us walked in arm in arm, faces down, just bawling bef -- like and we walked up to the coffin and just all almost just collapsed together and just wept. >> reporter: detectives discreetly sent an officer to the funeral home to observe. if tom's death was a homicide, they wanted to keep an eye on linda, but they also needed to find out if tom had any enemies. >> from speakin' to everyone, including her, tom was just a great guy. he was a middle-class man, hard working, loved his family, would do anything for them. we couldn't find any enemies -- in the world that would wanna do anything against tom. >> you had a real mystery you had to solve here. >> oh, absolutely. >> reporter: investigators were

interested in speaking to anyone close to tom, including his good friend who raced to the scene that morning. gilberto nunez was his full name and he was a prominent, local dentist, originally from the dominican republic. >> how long, i guess, have you known him? >> we be --i mean, i've known him for four years but we were starting a friendship around three years ago. >> okay. >> reporter: gil seemed to know a lot about tom's life, his work hours, his marriage, even his medical history. >> any medical conditions that you know of? >> yes. that i know of, he had sleep apnea -- >> reporter: investigators also fished for information about tom's wife. >> how's linda doing, i guess? have you talked to her since tuesday? >> yes. oh, yes. >> yes? >> yes, i've been there. i go to the house and stuff. >> okay. how's she doing? >> she's not doing too well. >> yes? >> she's very --i mean, she's really, really bad. she's in bad shape. >> reporter: but that wasn't all gil had to say about linda kolman. he had something far more interesting to share with the

detectives. >> i don't know if you guys know but, anyway, me and linda we had a relationship, so. >> okay. sexual relationship, i'm assuming? >> yeah. >> what's that moment like when he reveals he's having an affair with linda kolman? >> i think it caught us all off-guard because that was the first time we discovered thatwe had no reason to ask him about that type of relationship with linda. >> how long ago did that start? >> about a year. >> a year, okay. >> reporter: and gil revealed yet another detail that was even more surprising. >> did tom know about that? >> oh, yeah. >> he knew? >> he knew about our relationship, yeah. >> okay. >> he found out sometime in the summer. >> reporter: gil said that not only did tom know about the affair, the two men continued their friendship. >> and he saw that i was honest about it, and he was honest about it, so we got pretty close. i mean, to the point of, like, he got me into football, which i

didn't have a clue. >> how crazy is this, though, that tom continued to hang out with gilberto? they stayed friends even after he finds out he's sleeping with his wife. >> better man than i am. it's just not the norm. it's not something that you see. >> i mean, is your head starting to spin a little bit? >> we're trying to get ahold of what we got now because it, you know, stemmed from - - unattended death in the parking lot of a fitness club to now we got all this. so and within days, the -- things are starting to pile up. >> now. i would imagine you, more than ever, need to talk to linda kolman. >> we do. >> they did wanna talk to me. a few days after. and one of the first questions was, "what is your relationship with gilberto nunez?" coming up --

>> did he kiss you while you were in the chair? >> yeah. which blew me away. >> you're just living in almost two different lives? >> i had real life and i had fantasy life. >> passion, secrets, anger. >> he comes right at me with it. what the hell is going on? >> it's scandalous. imt i said this is what's been going on. >> when "dateline" continues. i'm just a normal person who got an awful skin condition. with uncontrolled moderate-to-severe eczema, or atopic dermatitis, you feel like you're itching all the time. and you never know how your skin will look. because deep within your skin an overly sensitive immune system could be the cause. so help heal your skin from within, with dupixent. dupixent is not a steroid, and it continuously treats your eczema even when you can't see it. at 16 weeks, nearly four times more patients taking dupixent saw clear or almost clear skin compared to those not taking it, and patients saw a significant reduction in itch.

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>> i told 'em everything. i didn't care anymore. at that point, i wasn't hiding a thing. >> how did you meet gilberto nunez? >> i met him at my son's kindergarten orientation. >> he had a child in the same kindergarten class. >> he had a child in the same kindergarten class. right. >> a son? >> yes. >> reporter: that was in 2009, gil was married then. and the two couples started socializing. >> we all seemed to like each other and we're friendly and, they would just say, "hey, wanna go out to dinner," whatever, and okay. >> and then, you started to get to know him better? >> over time, yeah. >> through school events, or? >> through that and then, our sons both did karate together. they were in the same karate class. >> reporter: tom and gil also hit it off and became close. talking sport, and watching giants games. and like tom, gil was a hands-on dad. ' he went to all his son's karate classes, where he would see linda.

>> so gil and i would sit next to each other and just talk. >> and this was, like, three times a week for an hour. >> what was it about gilberto that you liked? >> very friendly, very personable. >> reporter: a year went by before linda says she realized something was happening between them. >> every time he would leave, he would give me a kiss goodbye and -- >> on the lips? >> for him to give me a hug and a kiss on the cheek, you know, "see ya next week." kinda thing, really wasn't that big of a deal to me. like, it was kind of his culture but then as the weeks started goin' by, and i noticed when i was leaving, the kiss was no longer on the cheek. so i would go back to my car, like, "was that an accident?" >> lingering or just quick? >> no, fairly quick. >> reporter: linda said nothing to her husband, and she and gil never discussed whatever it was that was going on. until one day he finally said it. >> he actually called me one night. he basically was like, you know -- you know, "i can't get you off my mind, you're beautiful."

and, you know, "i just -- i adore you." and i was like, "oh." >> that's a hot potato right there. >> yeah, yeah. so from then, he started just textin' me. here and there we would talk, and it just progressed. >> did you think he was handsome? >> not really. [ laughter ] i'll be honest with ya. but he had -- he had a way about him. he had a very smooth, i wanna say, almost sexy way about him. with the -- with the accent. >> latin thing goin' on. >> yes, yes, totally, totally. it's his personality was sucking me in. >> reporter: it was early 2011. both gil and linda's marriages were going through rough patches. >> in all honesty, you know, tom and i, we were havin' some struggles in the home. >> what were you struggling with? >> i think probably the same stuff that every marriage after ten years struggles with. you know, paying the bills,

workin' two jobs. >> real-life problems. >> yeah, just -- yeah. and they were stressful. >> so was -- was gilberto a little bit of an escape for you? >> yes, yes. that's a really good way to put it. >> how does it finally get acted upon? >> i went and had some dental work in his office. so then you can imagine once i'm there and i'm in the chair and next step. >> did he kiss you while you were in the chair? >> yeah. which blew me away. the fact that this dentist, this smart guy, this, you know, smooth guy who seems to have everything,would even want to kiss me, or choose me. like, i just don't think of myself as someone -- why would he be interested in me, you know? >> was it passionate? >> yeah. >> reporter: pretty soon, they were meeting for sex. and by spring, gil had separated from his wife and was living in an apartment above his dental

practice. >> you had a busy life, a job, husband, children, in a small town. how are you carrying on this affair? >> still was the wife and the mother. i was home for my kids every night after work. and i would see him lunchtime. >> reporter: linda thought it was a well-kept secret. but maybe, not so much. a few months into the affair, someone tipped off tom with an anonymous text message. >> he comes right at me with it. you know, "i'm getting these texts that you're with --" you know, "that you're with gil. what the hell's goin' on?" >> it's so scandalous. >> and i said, "this is what's been goin' on." i -- i cleared the table. you know, "i have been having an affair. it was with him." >> was there any part of it that felt, i don't wanna use the word "good," but you got it off your chest, you weren't carrying -- >> yeah. >> -- around this secret anymore? >> it did. because then, because then at least i could talk to tom about it. at one point he said to me, linda, i can see he has some

kind of hold of you. he's like, i see it. and he did. >> reporter: and linda told us what detectives had found so hard to believe. >> how did it affect tom, the fact that it was gilberto, and he was friends with both of you? >> strangely enough, they still continued to be friends. >> that is so hard to grasp. >> i know it is. but they did. they cared, they cared about each other. they were, like, buddies. >> tom would invite him over for sunday dinners. i know it sounds nuts. >> yeah. >> i know it does. >> a little bit. yeah. >> i -- i know. >> and what are -- how are you handling that? i mean -- >> i'm just, like, in the middle, like, "what do i do?" >> you're the object of both of their affection.

>> yeah. and i loved them both. we'd say, "well, you know, we don't have to decide tomorrow. we have to just take some time and figure this out, you know?" >> reporter: linda says tom didn't pressure her to end the affair. to the contrary, he gave her the time and freedom to continue seeing gil and sort out her feelings. >> you're just living in almost two different lives. >> yeah. >> but they've intersected. >> i had a real life and then i had fantasy life, basically. >> reporter: but everyone in the triangle knew it couldn't last. linda had to make a choice, gil or tom. and a few weeks before tom's death, she did. coming up. her husband or her lover? >> he threw me on the bed. >> who would linda choose? had she and gil been telling police the truth? >> maybe linda wanted tom out of the way so she could be with gilberto? >> no question.

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>> reporter: it was just a few days after her husband's death when linda admitted to detectives that yes, she was having an affair with her husband's best friend. >> for a little bit of time there, it was me, tom, and gil really tryin' to -- to decide what we wanted to do, or what was i gonna do. they were letting me decide, you know? >> reporter: for months, linda's affection ping-ponged between the two men. that is, until her october wedding anniversary rolled around. she and tom decided to take the kids away for the weekend. >> i think it was really that weekend that i realized -- that i just want -- i just wanna be with my husband. [ light laughter ] he's my best friend. i love him. i don't want -- i don't wanna do this anymore. i've been stupid and foolish and ridiculous and it's -- i don't wanna do it anymore. >> reporter: you chose tom? >> i chose tom.

>> reporter: a couple of weeks later, it was thanksgiving. still on friendly terms, gil shared the holiday with tom, linda and their family. monday, linda met with gil one, but decided to postpone telling him their affair was over. >> reporter: what was that discussion like with gilberto? what did you tell him? >> the holidays are here. we have all these kids. like, we can't -- you know? "after the holidays." and he was, like, "okay, i'll wait for your decision," you know? >> reporter: do you think he knew? >> hindsight, i think he knew -- [ sighs ] probably by my body language. and just him knowin' me as well as he did, that he was losin' me. >> reporter: that night, linda felt she and tom were back on track. >> i remember comin' upstairs and he picked me up and threw me on the bed and was, like, ticklin' me. i think we both just felt like there's light at the end of this

tunnel. and this is the old us. we're happy and silly and -- and we're gon -- we'll get through this, you know? >> reporter: the next morning tom was dead. and investigators were now learning details about his complicated personal life. a bit of a soap opera going on here. >> funny thing is, prior to meetin' you guys, we said this is a "dateline" case. >> reporter: and here we are. [ laughter ] >> here we are. >> reporter: despite what they heard from linda and gil, investigators were somewhat skeptical that this love triangle really had no jealousy or resentment. d.a. investigator bill weishaupt. >> we had to try to determine, was there some type of relationship that we weren't seeing between the victim and nunez? what was going on between the two of them that they would all -- that tom kolman would allow the sexual relationship to continue between his wife and nunez? >> reporter: did you have to think of the scenario that maybe linda wanted tom out of the way so she could be with gilberto?

>> no question. that was top on the priority list. >> reporter: and the first question for investigators -- did linda or gil drive a white suv? detectives knew that linda didn't. but gil did. he drove a white nissan pathfinder. i mean, there are a million white suvs out there. >> sure. >> reporter: once you think about it and you start looking, they're everywhere. >> oh, absolutely. >> reporter: a coincidence, but a suspicious one. detectives were also remembering how gil showed up at the scene of tom's death to console linda, and his reaction struck them as odd. it was described as that he was hysterical, almost jumping up and down like a pogo stick. >> very dramatic. not a common reaction that you would see. >> reporter: if it's a good friend, though, who died, is that not possible that someone would have a very hysterical reaction to that? >> you do see strange reactions from 'em, but i believe his reaction was more than overdramatic, would i say. we kept in the back of our heads for later on.

>> reporter: both linda and gil told police the affair was now over. but investigators weren't so sure, and began watching them closely. >> there was electronic surveillance in terms of constantly monitoring their phone records, their computer records. and we also had a -- a gps tracker on nunez's car for a while. >> reporter: what were you hoping to find with that? >> we just wanted to determine whether, in fact, they were still together, if they were together at all. >> reporter: it looked like gil and linda were telling the truth. after weeks of watching them, police found no signs they'd been together since tom died. phone records also proved tom and gil were indeed friendly until the end, texting each other throughout that last giants game tom watched. and gil, like tom, was well-respected around town. >> he works hard, and he is not interested in money, as far as i can tell. >> reporter: zach sklar is a

patient of gil's and has always admired his generosity. >> does a lot of volunteer work in poor areas. >> reporter: did he ever say why he likes to do that? >> i think he's a man who cares. it's as -- as simple as that. i mean, he cares about his patients. and he cares that -- about, you know, people having access to good dental care. >> reporter: he was a member of the local chamber of commerce, a volunteer firefighter, voted one of the top hudson valley dentists five times, and chosen to endorse products in online ads. >> i'm dr. gilberto nunez. i'm a practitioner in kingston, new york. >> it was a very thriving practice. we were v -- we're very busy. >> reporter: his office manager, irene prehn, has worked for gil for 13 years. >> he's always very positive and very upbeat, very kind. he's a pleasure to work for. >> reporter: and everyone else police spoke to said the same. gil nunez seemed to have nothing to hide. what's more, after weeks of investigating, there was still no clear cause of death. so all investigators could do was wonder if the love triangle

was just an interesting story that had nothing to do with tom's death. but that would all change when the toxicology report came back, and it was a shocker. coming up -- >> i'm in the room with the detectives and i was like, no. >> what had happened to tom kolman. >> you had never seen it before? >> this wasn't a common thing. >> this was now a murder investigation. >> 100%.

>> this wasn't a common thing. >> this was now a murder investigation. >> 100%. or juice or some type of substance that could mask the taste of it. because it's a very bitter, bitter taste. >> reporter: and tom's autopsy had shown liquid in his stomach, that might have been coffee. >> we have -- now have a gentleman who is friends with the family, is having an affair with the wife, drives the same type of vehicle that we have on that video next to our victim the morning he's found.

>> reporter: this is now a murder investigation. >> yes. >> 100%. >> reporter: they called linda back down to the station for more questions. >> they asked me if i knew, you know, what drugs were in tom's system. they asked me, you know, more about the relationship with gil. this -- they asked me what i knew of that morning. >> reporter: they also decided to tell her about their suspicions that they believed tom was murdered and her ex-lover, gil, was their prime suspect. >> i found it hard to accept because in my mind, he loved us. he loved me. he loved tom. would he do that? would he do something like that? >> reporter: was a part of you saying, "oh, he couldn't have done this"? >> when i first found out about the midazolan and i'm in the room with the detectives and, you know, they were, like, "do you think he could've --" and i was, like, "no." you know, i was, like, "he would never do that to him." >> reporter: but after digesting what investigators told her, she realized there were signs of

trouble with gil. and over several more talks with police, she began revealing details that suggested their love triangle was far from tension-free. in fact, linda says gil had made it clear he was making long-term plans for them. he even bought her a ring. >> we were out having dinner and he proposed and i said, "i can't." >> reporter: how did he take that? >> "well, i know, i know, i -- i know, we got a lot to get through. but, you know --" and i said, "yeah, you're a little premature with that." >> reporter: it looked to investigators like gil was growing impatient. maybe eager to get tom out of the way. remember those anonymous texts to tom, the ones telling him about gil and linda's affair, she told police they came from gil. and when she found out, she confronted him. >> i was absolutely furious. >> reporter: what'd you say to him? >> i just screamed at him, like, "who the hell do you think you are?

why would you do this?" >> reporter: very, very devious. >> very, very. >> reporter: according to linda, gil cried, said he only did it because he felt tom should know the truth. she said he begged for forgiveness, and even threatened to harm himself. >> tom felt bad that he felt suicidal. he, you know, tom was that kind of guy. you know? i know this is a really crazy situation we're in, but i'm not going to let him kill himself over it. like, we'll work this out somehow, you know? >> reporter: linda says she was still worried that gil was suicidal and that's why she decided to postpone telling him the affair was over until after the holidays. she seemed sincere, but investigators had to wonder if linda and gil had plotted together to get rid of tom. did it ever enter your mind for a second, "i hope they don't think that i was in on this with someone or that i had something to do with this because of the affair"? >> not really. i had the affair, but no way in hell would i ever want harm done to my husband ever, you know? and i, you know, assumed if i was going to be -- need to be

eliminated -- let's do it. >> reporter: detectives went so far as to check out linda at her job. she worked at a hospital where beep goes off ] now that you have new dr. scholl's massaging gel advanced insoles with softer, bouncier gel waves, you'll move over 10% more than before. dr. scholl's. born to move. [ soft piano music playing ] mm, uh, what do you do for fun? -not this. ♪ -oh, what am i into? mostly progressive's name your price tool. helps people find coverage options based on their budget. flo has it, i want it, it's a whole thing, and she's right there. -yeah, she's my ride. this date's lame. he has pics of you on his phone.

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>> not really. i had the affair, but no way in hell would i ever want harm done to my husband ever, you know? and i, you know, assumed if i was going to be -- need to be eliminated -- let's do it. >> reporter: detectives went so far as to check out linda at her job. she worked at a hospital where she might have had access to midazolam. >> we made sure all the midazolam that they had was accounted for during that time period. >> reporter: they also asked her to take a polygraph test. she took a polygraph? >> yes, she did. >> reporter: pass? fail?

>> passed. so she was ruled out, in -- in our eyes. >> reporter: that left one person policed needed to talk to again, her former lover, gil. and this time, they planned to confront him with all their suspicions. >> right there we stop. right there we stop. coming up -- >> was that mystery suv really gil's? >> your car is on the road and you were driving it. >> and the sedative in tom kolman's system. >> i looked into -- >> reporter: ulster police had been keeping an eye on local dentist, gil nunez, since they learned he'd had an affair with tom kolman's wife. but now they believed tom's death was no accident and suspected a medical sedative was somehow to blame. so they decided it was time to bring gil in for another talk. >> are you and linda still -- >> we're close. >> it woulda lasted approximately seven hours. >> reporter: that's a long time. >> it was. there was a lot to cover. our biggest thing was the midazolam. the other thing was the vehicle. >> reporter: a team of investigators took turns confronting gil. they told him they had a video proving his s-u-v was at the scene. >> i never went to that gym. i never, you know, nothing, so i wasn't there, so that's not -- >> but if i -- but if i look you straight in the eye and i tell you that i know you were there? >> then i'm telling you that you don't know because it's not true. that is, you know, all in the truth. >> so you think i would lie? >> well i think you are lying to me, yes.

yes, totally. >> reporter: were you 100% sure that that was his white suv? >> was i 100% sure? i was 100% sure. but i could not physically give you a license plate to confirm that, no. >> reporter: and when investigators asked gil for his alibi -- >> i was home alone. >> okay. >> i'm always home alone. i live alone. >> reporter: he was all alone? >> all alone. >> reporter: this isn't -- this isn't the strongest alibi. >> it's no alibi. >> no alibi. >> reporter: but what about the sedative found in tom's system? gil didn't know it, but while he was being questioned, police were at his office, executing a search warrant.

and inside an emergency kit, they found two vials of midazolam. at first, gil denied knowing anything about midazolam, which also goes by the name versed. >> so you don't keep midazolam in your practice? >> what? >> midazolam? >> midazolam? >> yeah, versed. versed. >> no. we don't use versed. >> reporter: and with that, investigators thought they'd caught the dentist in a lie. they kept pushing, as gil tried to explain how the drug might have gotten inside that emergency kit. >> i don't go in there. i have never been in my emergency kit. because, whatever comes in the emergency kit, it's in there. >> okay. >> so -- >> fair enough. >> so it's easy. that's easy. >> so by all means, your fingerprints certainly shouldn't be on it, then? >> on what? on my emergency kit? >> on your midazolam. >> oh, if i put it in there, yeah. >> it wasn't until we said, "well, what if we find your fingerprints on those midazolam bottles?" at that point in time, his story changed. >> we went from original denial of not knowing anything about it to now he's handling it. >> they send it to me. and i put it in there, and the rest of them, they get tossed. >> okay. so let me just say this, then. if there's midazolam in the emergency kit -- >> okay. >> then your fingerprints would be on it, because you put it in there. >> yeah. >> reporter: and when investigators asked gil about those text messages to tom,

tipping him off about the affair, he had an explanation for that too. >> i would say, okay i'm going to try to figure out how to let him know. >> yeah. >> because if he was me, i want to know. i wouldn't be, you know, this. so i guess he took that as a sign of, like, courage and a sign of you know, my friendship. >> in one breath you're saying that you care about the guy. >> yeah. >> but, in a second breath, you want to get rid of the guy because you want to have a relationship with his wife. >> i don't want to get rid of him. there's no reason for me to get rid of him. i was in a -- >> sure there is. >> no. >> reporter: but investigators weren't buying it, and the mood in the room turned tense. >> so you're not his best friend. it's almost insulting when you say you are because if you were his best friend you wouldn't be [ bleep ] his wife and then sending text messages trying to break them up. >> i didn't send text messages . so you can be unstoppable. now improved! better tasting! feed your cells today.

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>> reporter: for nearly seven hours, investigators tried to rattle gil. >> [ bleep ] you. you're so full of [ bleep ]. telling me you didn't drive the car down the road. right there we stop. right there we stop. right there we stop, because your car was on the road, and you were driving it. everything else you said back there is bull [ bleep ]. >> reporter: through it all, gil stayed calm. and never asked for an attorney. >> i have nothing to hide. i have nothing with anything that is in my office or anything like that. i have nothing to do with whatever was in tom's system. i had nothing to do with any of that. >> reporter: did you give him a polygraph, as well? >> we offered. >> reporter: did he take it? >> no. the next day after that interview, we were contacted by a lawyer stating that there'd be

no further contact with his client. >> reporter: meanwhile, linda was reeling from all that police had told her. from the images of the white s-u-v in the video, to the drug in her husband's system that a dentist like gil would have access to. like investigators, she now believed her lover had killed her husband. >> i didn't ever wanna s -- speak to him again. >> reporter: but saugerties is a small place, and within days linda says she found gil waiting for her outside a chinese restaurant. >> he's sittin' in the parkin' lot and gets out of his car and starts screamin' at me and we'd get in a huge fight. and he's, like, "they're tryin' to pin this on me and they say you were involved." and i'm, like, "i wasn't. you did this. get away from me."

>> reporter: he was saying that the police were saying you were involved? >> and i was, like, "okay." you know, "liar," and he was, like, "i didn't, i didn't." >> referee:. >> reporter: but while both linda and the police were convinced gil was behind tom's death, investigators had no solid evidence. that grainy video didn't conclusively put him at the scene and they couldn't prove the sedative found in tom's system came from gil's office. the district attorney told his chief investigator they didn't have a case. >> we didn't have the evidence that -- that i felt or that my boss felt was compelling enough to put before a jury. >> reporter: but the investigation wasn't over. detectives were hoping they would find gil's d-n-a in tom's car and link him to the crime scene. while they waited for those test results, they let tom's family know they were investigating the death as a homicide. tom's ex-wife, michele, called linda for an explanation. >> linda told me she had had an affair with gil. she was crying on the phone,

crying that this had happened and she didn't use the word, responsible, but i know that's what she felt. >> reporter: tom's daughter jillian, who'd been close with her step-mom, was now furious. >> why would you do this, how could you be so irresponsible, just mad really and confused and trying to process, it took a long time to process. i stopped talking to linda at that point. >> reporter: linda's sister was also finding out about the the affair for the first time. >> she was just very sad and very upset. and i think embarrassed or ashamed for having been in a relationship other than her marriage. >> reporter: what did you tell her as the protective older sister? >> it's not your fault. she's blamed herself from that moment on. you didn't choose this. people have affairs. millions of people every day. and no one deserves this. >> reporter: tom's parents were stunned by the new direction the investigation was taking.

>> reporter: you go from thinking that your son likely died from natural causes to now there's a murder investigation? it just seems like something that wouldn't happen. >> just pilin' the crap right on top of you, right after another. >> reporter: to you. >> it was just, you know, what else are they gonna tell me now? >> reporter: did you call linda? >> no. >> reporter: why did you decide to just let it be with her? >> well, we were so devastated by the news, we didn't know how to deal with her. we didn't know what to think. >> if i called her and i spoke to her, i'm only gettin' one side of the story. my son's not around to -- to tell his side, or anybody. you know, so i figure, "well, if i ask her, i don't know what i'm bein' told." >> reporter: you must've been so angry. >> we were angry. we were sad. but you know, you -- we've lost a son. nothin's gonna change that. but we just wanted answers. >> reporter: investigators wanted answers too. but when the d-n-a results came

back, a new question was at the center of the case. >> that was not only important, that was a showstopper. coming up -- the new evidence. it was a showstopper all right. >> i said we're not going to go forward with any indictment. we're not going to go forward with any arrest. >> would it clear gil nunez? >> it wasn't possible that he would do anything of that nature. >> when "dateline" continues. moderate-to-severe eczema, or atopic dermatitis, you feel like you're itching all the time. and you never know how your skin will look. because deep within your skin an overly sensitive immune system could be the cause. so help heal your skin from within, with dupixent. dupixent is not a steroid, and it continuously treats your eczema even when you can't see it. at 16 weeks, nearly four times more patients taking dupixent saw clear or almost clear skin compared to those not taking it,

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>> reporter: tom kolman had been found dead in his car, with his shirt loosened and his belt buckle undone. at the time, investigators didn't give his appearance much thought, but almost a year later, it became crucial to the case. >> we got a dna report back from the lab that indicated there was an unknown male's dna on the inside of the belt flap of mr. kolman near the belt buckle. >> reporter: did you test this dna against gilberto nunez? >> yes. it was -- >> reporter: was there a match? >> not -- it was not his. >> reporter: no match? >> no match. >> reporter: where do you go from there? i mean, that is a -- >> that's a show-stopper. nothing moves in this investigation unless we can determine who that is. >> an unknown john doe. and that's a problem for me. >> reporter: holley carnright is the ulster county district attorney.

>> i said, "well, we're not going to go forward with any indictment, we're not going to go forward with any arrest until i have the answer to that. investigators collected d-n-a samples from all the first responders to see if they could have accidentally left their d-n-a at the scene. and they considered another possibility that the d-n-a belonged to an accomplice. >> we were also trying to get samples from people we had identified that were close to nunez. that's a little trickier -- because you just can't walk up and ask for the dna. we call it cast-off dna. and you would conduct a surveillance of those individuals and wait for them to discard an item that would most likely have their dna and then you collect that. >> reporter: what kind of items did you collect? i think there was a cigarette butt and maybe a can of soda. over many months, all the samples were processed, but it turned out to be a complete bust. >> it identified no one. >> reporter: it's not the first responders. it's not gilberto nunez. who is it? >> at that point, i was banging my head against the wall. >> reporter: linda was also growing frustrated.

she was now a widow, a single mom, shunned by her husband's family and eagerly waiting for a break in the case. >> reporter: a lot of time passed without an arrest. >> torturous. >> reporter: every day are you wondering, "is today the day or is it never going to happen"? >> you would kind of get through a point where you'd say, "okay, we're going to live our lives and when it happens, it happens," you know? and then they'd need something from me. and i'd get pulled back in again. >> reporter: one of those times police met with linda to explain there was a problem with the original autopsy. turns out it was incomplete because back then, no one suspected poisoning. many samples like the contents of tom's stomach that might have proved midazolam as the actual cause of death weren't saved for testing. so the d-a's office decided to do something radical. >> he said, "we need to exhume tom's body tomorrow." i just started sobbing.

and i was, like, "oh my god. i feel like the man can never rest in peace, you know. >> reporter: in fact, the medical examiner exhumed tom's body twice to do additional testing. >> reporter: there wasn't just one exhumation in this case. there were two. why twice? >> well we were going to do whatever it took to get the evidence that we needed. >> reporter: meanwhile, gil was free his dental practice thriving. the public had no idea he was a murder suspect, but he did confide in his staff. >> and i remember him telling us that, you know, he was innocent and that we needed to just work hard to keep the, you know, the office opened. i knew the kind of person that he was. and it just wasn't possible that he would ever do anything of that nature. >> reporter: so gil's life moved on a year turned into two, then three -- >> it's been, you know, very

hard for him. i think the only way he's been able to keep going is the fact that he knows he's innocent. >> reporter: he fell in love again and got married in the dominican republic. >> they were married on the beach. it was -- very beautiful. and with all his family. and closest friends. he was -- very, very happy. >> reporter: time was more cruel to the kolman family. brad, tom's son from his first marriage became depressed after his father's death and committed suicide. he was just eighteen. >> brad made an attempt on his life with sleeping medications. and all i could say to him was, "why? why would you do this to yourself and to us?" >> and his answer was, "i just wanted to go to sleep and wake up with dad." three months after that, he did commit suicide. >> he just wanted to be with him. so he made a decision. >> reporter: at this point now, you have this affair, this

horrible choice, that has now led to, potentially, to two deaths. >> it hurts, hurts a lot every day. >> surreal. i remember just staring at the programs with his picture and bradley kolman and the dates and just like telling myself, "you're at brad's funeral right now." it became upsettingly familiar. i mean, i felt too comfortable at the -- at a funeral setting and i realized, "this is just not -- this isn't fair. i've -- i'm getting too good at receiving bad news. >> reporter: through it all, the

d-a never gave up on tom's case. we're conducting these other parts of the investigation, we're developing video information. we're looking at the car, we're doing some pretty interesting things -- with regard to the vehicle. >> reporter: but the unidentified d-n-a was their biggest challenge. investigators gathered the brightest minds from the state crime lab to ask for advice. >> and one of them said, "have you checked the autopsies that were done before?" >> reporter: before tom kolman? >> before tom kolman. >> reporter: same day? >> same day. i looked at this person and said, "kind of always thought that was a sterile environment." and she said, "well, you should give that a check." so, we did. >> reporter: sure enough they got a match. turns out the d-n-a belonged to the deceased male who'd been on the medical examiner's table before tom. so the d-n-a had nothing to do with the case, but it did mean that some evidence had been contaminated. >> reporter: what are you thinking when you hear that? >> well, i'm thinking a couple things. i'm thinking, "that's gonna be a problem at trial because of the contamination." but i'm also thinking, "thank god, we get a little break.

>> reporter: and after all the additional testing, the medical examiner finally had a cause of death, acute midazolam poisoning. investigators took everything they had to a special prosecutor and argued they were sure gilberto nunez had killed the man he called his best friend. >> i don't think that nunez was ever a friend to kolman. not for a minute do i believe that. he is a master manipulator. he lives to manipulate. i believe he drew tom in because he wanted to be closer to the wife and have access to the wife. >> reporter: nearly four years after tom's death, gilberto nunez was indicted for second-degree murder. how did that feel when you got that news? >> i cried.

we all cried pretty hard. it felt -- it felt good in that, you know, we're one step closer to justice for tom. >> reporter: but tough times were still ahead for linda. at trial, prosecutors were about to reveal new details about her affair. coming up -- >> i am not leaving you. not today, not tomorrow, not ever. >> intimate e-mails between lovers and maybe a secret identity. >> he pulled out an i.d. that said the cia on top of it. it had gil's picture on it. >> undercover agent? ♪ protect your pet with the #1 name in flea and tick protection. frontline plus. trusted by vets for nearly 20 years.

>> reporter: four and a half years after tom kolman was found dead in his car -- gil nunez, went on trial for killing the man he once called his best friend. >> i was glad to see him being exposed for what he truly was. >> reporter: the rest of the kolman family felt the same but were far from a united front. tom's parents still weren't speaking to linda and tom's daughter, jillian, had limited contact with her while in town

for the trial. >> i just knew i had to be there for as much of it as i could be. i needed that closure and i wanted to hear everything that i wasn't being told for all those years. >> reporter: gil's supporters were also there -- his new wife, employees and several loyal patients. zach sklar was one of them. >> why did you feel the need to be there? >> we live in a society w -- where you're innocent until proven guilty. i saw -- nothing that would lead me to believe that this could possibly be true. >> and so i went there to support him, to show him -- particularly because he is dominican in a very white area, that there are people who will support him. >> reporter: but the prosecution's case would be difficult for gil's friends to hear. the state's theory, gil killed tom because he wanted linda all to himself.

the special prosecutor summed it up on day one. >> ladies and gentlemen, obsession. >> it was an obsession furthered by manipulation and deception. >> reporter: to show jurors just how obsessed they believed gil had become, prosecutors read emails he wrote to linda. >> "i am not leaving you. not today, not tomorrow, not ever. i am not going to let you just walk away from me. never." >> reporter: linda took the stand and testified about how the affair began and lasted until right before tom's death. tom's parents couldn't believe the details they were hearing. >> we just assumed that it was a one-time episode between them. we didn't realize that it was ongoing for 11 months. we heard that in the courtroom. >> wow. that's amazing that you didn't know that. >> when you look back, you know, that first kiss, if she would've slapped him in the face or kicked him in the nuts, it -- it wouldn't happen. >> you believe that this affair is the reason that your son is no longer with us -- >> well, yes, if he didn't come into their lives -- tom would be alive.

>> reporter: in court, prosecutors portrayed gil, not just as a man desperately in love, but also as someone capable of outrageous lies. along with those anonymous text messages gil sent to tom about the affair, jurors also learned he sent texts to linda, posing as a woman named samantha. >> linda received some disturbing anonymous text messages from a person samantha telling her that tom and she, samantha, were having sex -- wild sex. >> reporter: and that wasn't the only fiction gil created. linda testified gil even told her he was in the c-i-a. >> he had an i.d. card and he said that he sometimes would put trackers in people's -- >> mouths? >> mouths. >> did you believe him -- >> okay. yeah. i -- i didn't think that much of it, honestly. he kinda showed me a little card and i was like, "oh"! >> reporter: linda didn't make

much of it, but prosecutors had another story they wanted the jury to hear -- a story they thought would show a darker side to gil's deceptions. >> "it's just not a good idea." >> reporter: nick monaco is a retired police officer and friends with a guy who worked for gil. nick testified that the friend came to him one day saying that gil wanted to pay them to go harass and intimidate tom. >> he said, "well, gil wants to know if -- you would want to accompany me to, you know, just kinda like scare the guy." >> and he goes, "we may pretend like we're from the c.i.a. or -- or something like that." >> "just as long as he -- he sees that, you know, you have a gun on you and -- and a badge." he goes, "if he sees the gun --" he goes, "you don't have to wave it around or anything or take it out." >> and he says, "well, you know, gil was in the c.i.a." i was like, "no, i -- i -- i didn't know that." he goes, "oh, yeah--"

>> did you believe that? >> no. and then, he pulled out an id that said, "the c.i.a." on top of it. it had gil's picture on it and his name. and then, it had this m -- badge in there that said, "special officer." >> the badge was -- was obviously, you know, from walmart or -- or kmart or something like that. it was definitely a fake. >> reporter: nick says he refused to participate and never heard about the plan to scare tom again. >> you have to wonder what -- what a juror makes out of all this. >> reporter: reporter james nani covered it for the local times herald-record. >> they're hearing about a love triangle, and poisoning, and death and homicide, and a dentist, and emails, and the c.i.a. >> reporter: police later found the fake c-i-a i-d on gil's computer and tacked on felony forgery charges. and on a computer server in gil's office, police found an internet search for the word "midazolam."

>> if thomas kolman had been sleeping -- >> reporter: the prosecutor suggested that gil, as a medical professional, figured out that tom's sleep apnea combined with the sedative could be a fatal combination. >> walk through your theory of what happened the morning of tom's death. >> the night before, i believe, gil and -- and tom had texted about meeting that morning. >> i think, at that point in time, gil wanted to meet up with tom because of the fact that he knew that he wasn't gettin' linda. gil got out of his vehicle and entered tom's vehicle. at that point, maybe he brought him a coffee. i mean, it's early in the morning. here -- "hey, bro. i brought you a coffee. we gotta talk." and a short time later, gil was driving away and tom was dead. >> reporter: but prosecutors faced a couple of obstacles. for one, the judge wouldn't let them use parts of gil's interview with the police because he had not been read his rights, so jurors never saw how gil initially denied to police he'd ever heard of midazolam. >> so you don't keep midazolam in your office? >> what?

>> midazolam? >> midazolam? >> reporter: and prosecutors still had to link gil to the crime scene. they wanted to prove the suspect s-u-v seen at the planet fitness parking lot, belonged to gil. >> so we're able to track the movements of this vehicle through this gauntlet of cameras. >> reporter: grant fredericks is a forensic video analyst and was the key to making that connection. >> and we can begin to make observations of the vehicle itself and the pattern. >> reporter: police gathered additional video from nearby businesses to get a better look at the white suv. grant then pored through a database of 18,000 vehicles that's used by the f-b-i. >> each manufacturer, has a unique way of differentiating their vehicles. the length of the vehicle might be a big longer. the shape of the windows will be slightly different from manufacturer to manufacturer. >> reporter: fredericks testified that gil's car was as close a match as he could find to the one in the security video -- a 2010 nissan pathfinder. and he told the jury, one more important detail.

the s-u-v in the video had a fog light defect, one that cast a distinct headlight pattern. >> what we're seeing from this vehicle is that it has this white light that is on the ground that moves in front of the vehicle. >> reporter: detectives tracked down gil's white s-u-v -- which he sold a few weeks after tom's death -- and placed it along the same route seen in the security footage. >> and sure enough, when we went out to the scene then -- when we did our tests, we turned the lights on and there was the pattern that was quite visible. >> reporter: gil's car had the same defect visible in the video. prosecutors thought it was just what they needed to place gil at the crime scene and tie all their evidence together. >> that was a unique feature to that vehicle. and it was still exactly the same a year later. i have yet to find another nissan pathfinder, color white, with those exact same issues. >> reporter: but of course, the defense was about to tell a different story and had witnesses in store that could destroy the entire foundation of

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>> reporter: as gilberto nunez's trial for second degree murder played out blocks away from his practice, the dentist tried not to let it distract him from his patients. >> even during his trial, he would come and see patients in the evenings. >> some days were better than others. he seemed to be doing okay. >> reporter: patient zach sklar never wavered in his support. >> do i have doubts about his -- whether he murdered someone? absolutely not. >> why are you so sure that there's not a darker side to gilberto nuñez? >> i'm not sure about anything. i think there's a darker side to

all of us. people are complex. but -- there's absolutely no evidence that the guy committed murder. >> reporter: in court, gilberto was represented by two heavy hitters from new york city, evan lipton and gerald shargel -- who had previously defended mafia boss john gotti. they argued that the prosecution's case against their client was pure fantasy. >> they say that gil is such a schemer, but the plot they've described here, it's like something out of a bad lifetime movie. >> reporter: the defense said if anyone was manipulating things -- it wasn't gil. it was linda. they read her texts to gil -- sent the very weekend she said she was rekindling her relationship with tom. >> "i love you, i miss you. miss holding your hand. that soft spot scar on your face. mwah mwah mwah." can you just picture it? you're there with your significant other, she's behind you texting her lover? they weren't repairing things. >> reporter: so gil had no

reason to kill tom, the defense said because he didn't think the affair was over. >> reporter: reporter, james nani. >> linda admitted on the stand that up to the night before mr. kolman died that they had still seen each other, they had still spoken via text. i think that weakens the prosecution's narrative that there is an obsessive person that'll do anything to get this person, to get linda to go back into his arms. >> the defense was trying to say that you're telling tom one thing, you know, that you wanna patch things up, you're telling gilberto another, stringing him along. >> yeah. it was -- >> was there any truth in that, or did you feel that was unfair? >> no. there was some truth to it 'cause, you know, i -- i was stringin' him along. we were playin' his game so that he wouldn't kill himself over the holidays. so yeah, it was just a dirty, stupid game. >> reporter: the defense set out to dismantle the rest of the prosecution's case point by point.

all that business about the c-i-a -- they said it was more like a joke, hardly criminal and irrelevant to the charge of second degree murder. and there was ample evidence that gilberto cared too much about tom to ever hurt him. >> tom kolman and gilberto nunez were best friends. did spend time together. did make plans. did talk about going into a business together. there was no motive whatsoever for this alleged murder. >> reporter: they stressed that none of the physical evidence linked gilberto to the crime scene. >> no dna, no fingerprints. >> reporter: as for that internet search for the word 'midazolam', the defense pointed out anyone in the office could have done it and they believed it revealed very little. >> not a search for a question about the drug. not how to kill with midazolam. a search that led to a wikipedia page. that search says nothing.

>> reporter: as for the prosecution's star witness, the forensic video analyst who placed gilberto's s-u-v at the scene, the defense said his findings proved nothing. >> even the expert doesn't say, "oh yes, i see in -- in the video surveillance it was tom kolman with gilberto in the car." no, he didn't even see if someone went from one car to the other car. >> reporter: the defense raised another possibility about who was in the white s-u-v. they reminded jurors, tom was found with his clothes disheveled and pants undone. and suggested that tom may have had some kind of liaison planned. >> reporter: an examination of his phone revealed that he had received an email from a hook-up website called be-naughty.com. >> the website that was found on his phone was benaughty.com, it was never the subject of any investigation in this case. >> the defense was essentially trying to throw some reasonable

doubt into the equation. "what role does this have to play?" it was left as an open question. >> reporter: but their main argument, the prosecution couldn't prove that gil murdered tom because they couldn't even prove it was murder. they challenged the medical examiner's conclusions, saying that despite all the tests, there was no way to know how much midazolam was in tom's system when he died. and the amount that was found didn't look like enough to kill him. >> the reality? his heart was a ticking time bomb. he might have dropped dead at any minute. >> reporter: the defense put on their own medical expert who said tom's death was more likely from natural causes. >> dr. sicirika. >> the defense was very succinct. they said they have one witness who looked over the records of mr. kolman, who looked over the autopsies of mr. kolman, and essentially says, mr. kolman had an enlarged heart, and that we think is the reason that he actually died."

>> the prosecutors, the detectives, they want this medical testimony to show a murder. what it actually shows is heart disease, a likely heart attack. >> the prosecutor wants the toxicology to support a theory of poisoning. what it really shows in a non-lethal dose of midazolam, a widely used, safe medication. >> reporter: as the case went to the jury, gilberto's supporters in court were more sure than ever that the dentist was innocent, but no one could be certain of the outcome. >> it doesn't matter if you're innocent or not. they can still sell you guilty whether you are or you aren't. you know, it all depends upon the jury. coming up -- >> did you both believe that was nunez's vehicle? >> i did. >> yeah. >> yeah. his car was there. >> a quick decision in the jury room and a storm in the courtroom.

>> i wanted him to look at me.

>> reporter: the case of the dentist accused of murdering his best friend was now in the hands of the jury. >> i was worried because, i mean, from day one, i had been told, "this is a circumstantial case and it's all in the hands of a jury. so while we will try our hardest and we do think it's a strong circumstantial case, we can never guarantee the outcome." >> what's the difference between that man that you got to know that you fell in love with, and the man you know now? >> the man i know, or see now is just a cold, dead heart who doesn't care about anyone but himself. >> reporter: tom's family hoped the jurors felt the same. >> i thought that the case went very well for us and that the defense didn't do a good enough job to place doubt, i was pretty

confident at that point. >> reporter: in the jury room, 12 men and women got right into it. fran kwak and joseph dolan were two of the jurors who debated the friendship between tom and gil. >> i believe they were best friends. >> you do believe that. >> oh yes. as odd as it may seem, they had a lot in common. they loved a lot of the same people. >> the police believe totally the opposite, that -- >> -- mhm. >> -- gilberto wanted to make you believe that they were best friends but they really weren't. so, you don't -- >> i wasn't so sure about that. >> what? about the friendship? >> that they were best friends. i mean, i just find it difficult to believe that. >> reporter: but if the friendship was confusing, they say the security video made one thing clear. >> did you both believe that was nunez's vehicle? >> i did. >> yes. >> we all said we -- that he had something to do with it. >> reporter: their deliberation didn't take long. after just 6 hours the judge announced there was a verdict. >> is that a good sign or a bad sign?

>> i was back at police headquarters at the time. and, and mike had texted me. >> was confident. i felt that a verdict was comin' in that soon, that they -- they would've decided it was guilty. >> if it happens too quick, it's not good. if it happens too quick, it is good." there's no rhyme or reason to it. >> so at that point we started praying. 'cause we just were like, "this is it." >> mr. foreperson, how say you to count one, charging the defendant gilberto nunez, with murder in the second degree? >> find the defendant not guilty. >> is that verdict unanimous? >> yes, sir. >> reporter: not guilty. and not at all what tom's family expected. >> it was utter heartbreak. it was almost five years of hope

and like the, the beautiful possibility of closure and leaving it behind, just taken it away. >> was that a tough blow for your family? >> absolutely. >> yeah. my family believes he had a hand in it. >> reporter: but of course, gilberto's supporter's felt the exact opposite, amazing relief. >> we were just crying all of us. we were just, like, clinging to each other and crying. it was years and years of just not knowing what's gonna happen. you know, we were just so happy. >> i was pleased that he was found not guilty. clearly, the jury did feel that there was not enough evidence to convict him. i felt that all along. >> reporter: so how did the jurors come to their decision? some came up with their own theory. that maybe gil did give tom the midazolam, but not with the intention of killing him. >> from the very beginning, i believed that nunez was there at the scene but as a friend to help kolman get some rest that he hadn't been gettin', and that he left, and everything was fine, and he was as much surprised-- with tom's death as anybody else was.

>> you formed that opinion right away? >> yep. >> first day? >> yeah. pretty much. >> reporter: as for the prosecution's medical evidence, they say it just didn't convince them of murder. >> what did you feel was the strongest point on the defense's side? >> that the midazolam -- >> -- yeah. >> -- was not in a amount that could have or should have done any harm. >> i believe that it very well could have been just to help him sleep. >> some people have criticized you for the six hours and change verdict time. >> 'cause it was so quick. >> right. >> yeah. we coulda went over it for another six hours and read the same stuff over and over again, and we woulda come up with the same result. >> same result. exactly. >> reporter: it was a bitter pill for linda to swallow. she may have had a hand in starting the whole thing but couldn't leave the courtroom without having the last word. >> lying piece of [ bleep ]! psychotic! sociopath!

>> i lost it. i was, like, "gil." i wanted him to look at me. say, "you're still a piece of [ bleep ]. and i just felt like on the way out the door, i had to say it. "he's a sociopa --." like, don't you -- like do you get that? does anybody get that? >> reporter: although gilberto was found not guilty of second degree murder, he was found guilty of the two forgery-related charges for the fake c-i-a materials. and could serve a maximum of seven years in prison. >> we still damaged him. he'll still be a convicted felon. it's not what i wanted. but he's not walkin' away completely free. >> reporter: gilberto nunez declined to be interviewed on camera. but invited us into his office. he told us in an email that he feels sorry for tom's family, and is angered by what he calls "the selective prosecution" against him. and is extremely disappointed by the forgery convictions.

and since the trial, gilberto has been convicted in an unrelated case. found guilty of charges connected to insurance fraud. and while the kolmans are united in their grief. the gulf between linda and the rest of the family remains. tom's daughter, jillian, has found a way to stay close to ryan, her half-brother, but it hasn't been easy. >> i do forgive linda. i won't forget what she's done and the effect that it's had on me. and she will probably never be close enough to me again to have that effect again but i forgive her. >> reporter: as she tries to move forward, linda says she's having a harder time forgiving herself.

>> do you feel that guilt still? >> every minute of every day. >> i know things have been strained with tom's parents. is there anything that you would say to them if they're watching this? >> just that i'm really sorry. and that i understand why they hate me. i totally understand it. i live with those same feelings about myself every day. and to anyone that this has hurt, any of tom's friends, his family, my family, anyone that's loved him. you know, for the role i played, i am deeply, deeply sorry.

manson has come to represent the malignant side of humanity. these people enjoyed killing. >> things the police had never seen before. >> sharon tate begged her, please don't kill me, please don't kill me. >> average kids from average american homes turn out to be the killers. >> he would dose them with lcd. >> 16, it's relative. >> charles manson stole lives. >> grief like you could not imagine. >> stole innocence. >> he looks beautiful, he looks happy and this draws a lot of people. >> and left a city living in fear.