it will be a lot of fun. hope to see you there. that's "all in" for this evening and this week. i could not believe it. i couldn't imagine anyone that would ever want to hurt her. i had no idea what could have happened. married to her high school sweetheart, family meant everything to her. >> it was always a lot of talk about children. she wanted grandchildren fast. >> it all went up in smoke the night she died in a mysterious and monstrous inferno. >> i found the remains of julie. >> shocking as the blaze was, it was nothing compared to what

investigators found in the embers. >> bullet. >> this woman had been shot to death. >> yes. >> the obvious suspects, neighborhood thieves. >> there were half a dozen house burglaries and assaults. >> investigators also dug into a favored theory. the husband did it. >> i was angry. i felt that the detectives were on a manhunt and after my dad. >> anyway, he was in another state. >> he was over 200 miles away. >> then a popped up text that might just be a clue. >> you could say she's driving events here. >> that's correct. >> the truth beyond twisted leaving behind smoking ashes and burning questions. >> i physically started shaking and i started crying. i want to know why. >> i'm lester holt and this is

"dateline." here's dennis murphy with "consumed." reporter: the canterbury hills subdivision in paducah, kentucky, is a good place to raise kids. tidy homes kept up by neighbors living ordered lives. so as the front porch lights winked out on just another day, what happened one cold january night in the wee hours was especially alarming. reporter: the canterbury hills subdivision in paducah, kentucky, is a good place to raise kids. tidy homes kept up by neighbors living ordered lives. so as the front porch lights winked out on just another day, what happened one cold january night in the wee hours was especially alarming. orange flames were licking the tree tops. a roaring, all consuming fire, was devouring one of the nice homes. >> it was awful, half of the house was gone.

>> reporter: what would rise from those ashes was far more than a fire marshal's investigation into cause. there would be a probe into the deepest roots of a treachery beyond most people's comprehension. >> it's not true. no way. >> reporter: what had they all missed? >> a monster. a liar. a cheater. >> he's destroyed my entire family. >> reporter: before it became charred rubble, the house was home to a longtime paducah couple, keith and julie griffith. church going, golf playing high-school sweethearts 36-years into a marriage that had produced two sons. aaron the older. >> they were very supportive parents. they were loving. they loved my kids.

>> reporter: aaron took after his dad, athletic, easy going, level-headed. younger brother zach was more of a firecracker like his mom. there was the time, for instance, in the sixth grade, zach grabbed a shovel and started digging a hole for a koi pond in the backyard. >> my parents come home. they're, like, "what are you doing?" i'm, like, "we're gonna have a pond." >> reporter: were they okay with it? >> yeah, they were fine. and they were kind of, like, "well, this is gonna be a nightmare." >> reporter: when aaron and zach flew the nest, the griffith's lives seemed to get only busier. they joined a motorcycle class through their church and frequently were a golf foursome with friends, craig and temple bradley. >> everybody that knew keith loved him. great guy. >> reporter: did he become your best friend? >> yeah, definitely. one of my very best friends. >> reporter: temple felt that way about julie, too. >> she had a heart of gold. she would do anything for you. but she also wasn't afraid to tell you exactly how it was either. >> reporter: did she get people's feathers ruffled? >> oh yeah. yeah but everybody loved her. >> reporter: after early retirement from the water company, keith found a second

career as travelling lawnmower salesman. which left julie to spend a lot of nights alone in the house. but keith never worried for her well being in a safe neighborhood, their own door watched over by their beloved great dane cleo. aaron's wife, ali. >> i know that for a long time, they didn't even lock their door. they would leave and go to dinner or go to town and leave the door unlocked because cleo was the guard dog. >> reporter: fulfilled as the griffith's lives seemed to be, keith and julie were transformed when aaron and ali brought into the world their first daughter, aria. >> when i had that first child it was the greatest day of her life, i think. >> julie lived for my little girl. she wanted to be a part of everything that she did. >> reporter: and julie was there for ali when she went into labor with their second daughter, analiese. her white knuckled dash to the hospital earned julie the affectionate nickname, nascar nana. >> the flashers were going and she was honking the horn and we -- >> reporter: and what is she saying to you? is she talking you through it? >> she says, "don't have a baby in my car."

she says, "keep your legs crossed, don't have a baby in the car." >> reporter: everything seemed to be going great for the griffiths in 2013. keith had weight loss surgery and dropped more than 100 pounds. julie was over the moon with two grand-daughters. but also that year came the rift. zach disclosed to his very religious, conservative parents that he is gay. >> it was definitely hard. i mean, it went from my mom was my best friend and calling up and talking to her multiple times a day to just being completely -- just completely shut off. >> reporter: julie visited zach that fall. they tip-toed around the elephant in the room but the time together gave zach hope. >> reporter: was that the step, as you look back, to patching things up between you and your mom? >> yeah. >> reporter: there was a way forward. >> there was definitely a way forward. we just needed more time. >> reporter: but then, came that cold night in january. >> 911, where is your emergency? >> uh. yeah. there's a house on fire in canterbury and there's not a fire truck here! >> reporter: a duty drov towahe griffith home, his dash cam recorder cahi this quick glimpse of the blaze. thene fire trucks arrived. mccracken county sheriff's detective matt carter received a call in the middle of the night. >> reporter: this is a bad fire? >> very hot. that whole left end of the house

was just completely consumed with fire. >> reporter: it took about an hour for firefighters to knock down the flames. hours more for them to make their way through the blackened wreckage of the house to what seemed to be the heart of the fire, the master bedroom. ghastly, what they would discover. what they found in the embers would rattle the neighborhood and shatter the family. >> everything was just consumed by fire to the point that things were unrecognizable. investigators make a pair of discoveries and realize they're dealing with both a tragedy and a mystery. >> he had recovered a projectile. >> a bullet? >> yes.

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>> reporter: daybreak revealed the grim aftermath of the blaze at 307 tudor boulevard. wisps of smoke rose from the black water-soaked wreckage that was once the griffith home. detective matt carter. >> this entire structure had crumbled. it was a pile of ashes that was on the ground. we didn't even know if anyone was home or not. we knew that they were in and out of town a lot. >> reporter: as firefighters carefully walked through what appeared to be the fire's epicenter, the master bedroom, their worst fears were

confirmed. julie had, in fact, been home that night. it was to the right of the box mattresses that -- we found the remains of -- of julie. they were unsure, initially, that it was human remains. we knew that there was -- >> reporter: even with all their experience? >> yes. everything was just consumed by fire to the point that -- that things were unrecognizable. >> reporter: as for keith? he was away, calling on customers in indiana. word of julie's death spread almost as fast as the fire had raced through the house. >> i'm getting ready for work, have the tv on in the background. >> we are live in the canterbury hills subdivision on tudor boulevard. >> reporter: then, temple bradley's phone rang -- it was a friend, who also knew julie. >> she said, "you know there's the fire." and i said, "yeah, i saw it on tv." and she said, "it's keith and julie's house." and i just sat there. >> reporter: did she know at that point that julie in fact was gone? >> she knew, and so she told me. >> reporter: temple's husband immediately tracked down keith as he was making the three-hour drive home from indiana. >> he said, "i'm on my way. i'm probably, you know, two hours away." i said, "are you all right."

he goes, "yeah, yeah." i could tell he was in shock. >> reporter: the news hit zach griffith particularly hard. since coming out to his mother, his relationship with her had been strained, and now this -- i guess you're just beating yourself up something terrible, that you'd been sideways with her -- >> yeah. and i know that if we were just given more time, that we would've been close again, that we would've been, you know -- that mom and son duo that we were. but we just -- we didn't have the time. it was ripped away from us and never get it back. >> reporter: aaron, the elder son, had more of a "take charge" reaction. >> i gotta take care of my brother. i gotta take care of my dad. >> reporter: you got logistics before grief? >> yeah. >> reporter: the news didn't even get absorbed? >> yeah. yeah. for me -- that's just kind of the way my brain is wired, i guess. >> reporter: within hours, the griffiths would head from all directions toward what used to be an anchor in their lives -- the family home. >> i just gave my dad a big hug, and we were both crying and we were like, "i can't believe

this." "what happened?" >> reporter: keith's good friend craig bradley was there to lend his support. and how was he doing? this is the first time you have a chance to see him eye to eye? >> i could just tell he was shaken. >> reporter: as if the news couldn't get any worse, the griffith's great dane cleo, along with the second pet daisy, had also perished in the flames. craig and keith walked the property surveying the damages. >> we get to the koi pond and he's like, "gotta get -- gotta get those fish outta there. julie would kill me if something happened to those fish." i was like, "you know, let's not worry about that right now." >> reporter: overwhelmed by loss, the griffiths were faced with the question -- how could this have happened? >> the first thought was that it was the new heating and air unit, it had just gone in. >> reporter: the unit had been installed just days before the fire, adjacent to the master bedroom. >> that was my very first thought. that somehow the new heating and air unit wasn't put in properly. >> reporter: faulty installation? >> yeah. >> reporter: as for the cause of julie's death, that was left to the county coroner's office.

deputy coroner ben bradford. >> what were you working with? >> a very, very charred body. i could not very well identify it being a person. >> reporter: the cause of death seemed obvious. but just to be sure, julie's remains were sent onto the medical examiner for an autopsy. what he discovered was as deeply troubling as it was unexpected. >> he had recovered a projectile in the -- the remains. >> reporter: a bullet? >> yes. >> reporter: suddenly, what was thought to have been death by smoke inhalation was now a homicide. closer examination revealed three bullet holes in all in julie's torso. the deputy coroner immediately called the sheriff's office. >> i said, "we need to get some people back to that house, because this is going to be a homicide." >> reporter: what'd you think?

wow? >> absolutely. >> reporter: lady in a nice neighborhood, good house? >> right. >> reporter: and now she's got three bullet wounds? that's right. on a who did it crime. >> reporter: back at 307 tudor boulevard, fire equipment pulled out as sheriff's cruisers pulled in. would the charred wreckage of a home, once filled with joy and laughter, now hold clues pointing to a killer? coming up -- could julie's murder have been a burglary gone bad? copd makes it hard to breathe. so to breathe better, i go with anoro. ♪go your own way copd tries to say, "go this way." i say, "i'll go my own way" with anoro. ♪go your own way once-daily anoro contains two medicines called bronchodilators, that work together to significantly improve lung function all day and all night. anoro is not for asthma . it contains a type of medicine that increases risk of death in people with asthma. the risk is unknown in copd. anoro won't replace rescue inhalers for sudden symptoms

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>> reporter: the theory that julie died by accidental fire had collapsed as suddenly as the griffith house itself. for detective matt carter, a 45 caliber slug recovered from julie griffith's torso turned the charred rubble into the scene of a homicide. so i'm guessin' your day's changed a whole lot here, detective, huh? >> it's changed a lot. >> reporter: despite more than a decade on the job, the detective had his work cut out for him. no hair, fiber, bloody footprints, none of that stuff. >> right. you've got an arson that's destroyed any chance of obtaining any of that from the scene. >> reporter: for detective carter, the most obvious theory: this homicide was the work of a home intruder. >> a burglary gone bad. >> reporter: somebody's lookin' for the laptop or whatever jewelry and thing goes down. >> right. we had had some burglaries within a few miles of this area. >> reporter: what? within weeks or months or -- >> within weeks.

within weeks. >> reporter: as police canvassed the neighborhood for leads and witnesses, the investigator also had to consider: the perpetrator may have been someone julie knew. >> you're not ruling anyone out or in. you're simply going through the motions. you're speaking to immediate family and first. and workin' your way out. >> reporter: the sheriff's department did not tell the griffiths julie had been murdered. >> we were not told anything by the police at that point. >> reporter: but anyone at the scene might have guessed foul play was somehow involved. >> there was just cops all over the property. >> reporter: so you said, "why are the cops here?" >> exactly. yep. >> reporter: naturally, the first person detective carter interviewed was julie's husband keith. >> first of all, we are, are sorry for your loss. >> i appreciate that. >> reporter: at first, keith talked about what everyone

perceived was the cause of the inferno: an accidental fire set off by a newly installed heating unit. >> you had a new gas pack put in tuesday? >> mmm hmm. >> okay. >> i mean it was a whole new system. >> reporter: keith explained the contractor was a friend of his who'd done the work just a few days earlier. >> they put a rush on it. i mean, you know, that's kind of what friends do for each other. >> okay. >> and i hope to god that this problem is not his. >> reporter: but eventually, without giving details, the detective revealed julie's death was no accident. >> the investigation's showing that, that foul play is involved. >> okay. >> i do not believe at this point in time that this was any kind of an accident. i'm going to ask for your cooperation on, on several things. okay? >> okay. >> reporter: one of the first things detective carter asked about was how keith and julie were getting along. >> any problems at all that y'all had or anything like that whatsoever? >> no, she's my best friend.

>> okay. >> i mean i know i mean that woman loved everybody. >> reporter: the investigator also asked keith for details about his business trip to indiana. >> what hotel? >> comfort suites. >> comfort suites? okay. >> didn't leave the hotel? >> i did leave the hotel, about 11:00 i went and got something to drink. >> and i left again about 4:00 and just went and, and got a doughnut and a coke. >> like i said, i get up pretty early. >> reporter: and what about weapons. did keith own a gun? >> i have a .45 acp in my work truck that i just got, and it's never had any, i mean it's never been loaded. >> reporter: as part of standard protocol, the detective asked for keith's clothes. they would be tested for gun shot residue. >> what you're wearing now, is that, was that fresh clothes from this morning whenever you? >> this is what i wore yesterday. >> reporter: before wrapping up the interview, the detective took a look at keith's cell phone. >> while i'm reviewing this phone, i see that he obtains a text message, an incoming text message from a lady by the name of deanna jaynes. >> reporter: ping, up comes a text message? >> that's correct. >> reporter: the message read: "did you make it home okay?" keith was quick to point out, his relationship with deanna was completely platonic.

>> she's more like a guy friend. >> reporter: no big deal? nothing sexual? >> no big deal, that's right. >> reporter: after that, keith was released to go and grieve with his family. detective carter, meanwhile, set out to verify keith's story. >> he had a receipt where he had stayed. >> reporter: so that puts him three hours away from this house fire. >> correct. >> reporter: the death of his wife? >> it showed his check-in time and check-out time. >> reporter: a quick check of keith's gun showed he was telling the truth about it as well. the gun looked like as though it had never been fired. so maybe he's not the guy. >> he may not be. >> reporter: so then who was? coming up -- the detective sits down with deanna. was she really like a guy friend to keith? >> you could say maybe she's driving events here. maybe she wants to get rid of the wife. >> that's correct.

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reporter: julie griffith's family had hardly had time to absorb the horrific news of her death in a house fire when disturbing rumors started reaching them that investigators thought her death was foul play. the sheriff's department kept details of the murder quiet for days. >> i could not believe it.

>> reporter: daughter-in-law, ali. >> i couldn't imagine anyone that would ever want to hurt her, much less set the house on fire, the dogs perished, i -- i had no idea what could have happened. >> no enemies. i mean, it made no sense. it -- just who would wanna kill her? >> reporter: after keith was released the night of his interview with detectives, he headed straight to his friends, the bradleys. they were floored to hear the line of questioning that he recounted. what was up with his marriage, his alibi, the gun he owned? >> he had been questioned to the point that he almost felt like that they thought he did some -- that he had done this. >> reporter: son aaron also got called down to the station that same evening and he, too, was questioned about his parents marriage. >> noticed anything lately in their relationship as far as any problems or anything like that? >> no. >> that you're aware of? >> no, no, nothing. >> was there any money troubles? was there any relationship things that we knew of? >> reporter: but to a person in the griffith's circle, the very

idea that keith might know something about julie's death was, well, just flat out crazy. >> i knew he didn't do it. >> there wasn't any way that keith was involved in this. >> i remember sittin' there and lookin' over at keith and just watching him for a while and finally i just said, "you can't even grieve, can you?" and he said, "no, they've taken it all away." >> reporter: the friends working theory was a botched break-in. they'd heard about the neighborhood's recent rash of burglaries. maybe that's what happened to julie? >> they'd come in and they startled cleo. >> reporter: dog started to bark and go for them? >> uh-huh. it caused julie to wake up and they got scared. and they shot her. >> it made perfect sense. >> reporter: but for detective carter, the burglary theory of the crime wasn't panning out. even as they sorted through the rubble, detectives at the scene found untouched valuables. two safes, a cache of guns and

julie's purse sitting in plain sight. >> reporter: you think an intruder would have grabbed it? >> you would think so. >> reporter: so carter set out to follow the most promising lead he had. who was this woman deanna? the text messager who wondered if keith made it home ok. he had described her as a "guy-friend." >> there was just somethin' about that text message that seemed to stick out. and it -- and it seemed to create that question of, you know, what's missing here? >> reporter: carter had called ahead to the authorities in the indiana town where deanna lived. they'd arranged to bring the woman down to an interview room. she was waiting. >> my name's matt carter. >> matt. >> reporter: deanna was about to tell the detective a story that would dramatically reshape his investigation. >> reporter: was she a "guy friend?" . it -- it was me than that. >> reporter: deanna shared the same wit storyus.

>> he wanted me to love him. >> reporter: deanna says she and keith first met years earlier at a vendor fair. she was the cfo of an i.t. company. keith, the road-warrior lawnmower salesman, had a booth there. >> keith was sitting there. and i guess i caught his attention right away. >> reporter: you'd noticed he was eyeing you, huh? >> right. i noticed he was staring at me. and so i kinda, you know, just smiled. >> reporter: she says he asked her to dinner. they quickly discovered how much they had in common. >> he talked about both his sons and being a grandpa. so i just really connected, because i had grown kids, too. >> reporter: after several dates, deanna says, keith expressed interest in a relationship, but she wanted to keep it just-friends. they stayed in touch but didn't see each other for awhile. then, just a few months back, he sent her a flirty text message. >> the text just said, "did you cast a spell on me?" and i'm like, i looked down at my phone, i'm like, "what? he says, "well, i was in a party last night, and this woman was chattin' me up." he goes, "and all -- all i could think about was you." >> reporter: deanna, who was in the throes of a traumatic romantic break-up, agreed to start seeing him again for dinners. and, she says, he seemed excited to show off the new post-surgery keith. >> he goes "you're not gonna recognize me." and he goes, "i've lost over 100 pounds."

and i said, "you have?" >> reporter: did he look okay? >> he looked fine. i mean he felt -- i think he was more confident, as well. >> reporter: deanna says keith now began aggressively courting her. showering her with gifts, flowers, notes of affection. it was all, she said, a bit much. >> he kept pushing for more. and i kept telling him, "you need to back off. you need to slow down, because i'm just not there." >> reporter: deanna says she couldn't put her finger on it, but there was something about keith that was holding her back. maybe it was the fact that he still seemed unusually bound to a woman he called his ex-wife. from the very beginning, deanna says, keith told her that he was divorced. >> very first conversation. >> reporter: "i'm a divorced guy." >> right. >> reporter: by the time she was

sitting across from detective carter in that interview room, deanna says she and keith had never been intimate but they were dating. and keith was talking long term. house-hunting for them. >> he said, "i don't want to scare you, but i want you to know that i'm looking for properties here in mooresville to buy, so, for us to be together." >> reporter: for the detective, deanna's story put a whole new spin on the investigation. keith griffith now seemed like a man with a very big secret. or, thinking like a homicide detective, was she the one with the secret? >> reporter: you could spin it another way and say, "w -- maybe she's driving events here. maybe she wants to get rid of the wife --" >> that's correct. we were open for that, being an idea or a possibility. >> reporter: in fact, the detective had let her tell her story without ever explaining the reason for his visit. now, he laid out his cards. >> was he not divorced? >> um -- no. he says, "first of all, keith's not divorced. according to him, he's been married to his high school sweetheart for 36 years." and i just broke down, because i -- i couldn't believe it. >> reporter: but, of course, there was more.

>> we are conducting an investigation, and this investigation involves what we believe to be a homicide of his wife. >> i was in shock. i was like, "oh my gosh." i couldn't believe what he just said to me. i had no idea. >> reporter: so you believed she had been played by this guy? >> i believe that she had. >> reporter: so, detective carter wondered, if keith griffith had manipulated and lied to this woman. had keith lied to him, too? maybe it was more about what keith hadn't said. rewind to that moment when the detective had dropped what should have been devastating news on keith. >> the investigation's showing that, that foul play is involved. >> okay. >> reporter: did he ask you the questions, "what happened? what are you tellin' me here? she was killed?" >> no. >> reporter: i mean, you'd expect that, right? "julie was shot by an intruder?

what's goin' on here?" >> that's right. there was -- there was no questions to that. >> reporter: but if keith griffith was somehow involved in his wife's murder, how on earth had he pulled it off? after all, he was hundred of miles away at that hotel the night of the crime. unless, of course, he wasn't. coming up -- a security video surprise. >> you're scrolling through the tape. >> going through, going through. >> what was your bingo moment? >> and then a twist rocks the entire griffith family. >> we were all frantic. we had no idea how it could have happened. >> when "dateline" continues. if only harry used some... ...bounce, to dry. he would be a less wrinkly, winning guy.

>> reporter: six days after the cold-blooded murder of julie griffith, family and friends gathered at her church to say goodbye. between the visitation and the memorial service, son, zach, was overwhelmed. >> just showed, like, what an amazing woman -- that my mom was, to have that many people come out just to say that, you know, they just wanted to give their condolences. >> reporter: to close friends craig and temple bradley, julie's husband, keith, was more emotional that day than they'd ever seen him. >> tears. >> tears. >> sadness. i'd never seen him cry, you know? in my life. >> reporter: but even as the griffith family mourned, zach and his brother were feeling uneasy about the investigation which seemed to be focused exclusively on their father. >> i was angry. i felt that the detectives, the sheriff's department, were on a manhunt, and they were after my dad.

and it -- >> because the husbands always do it? >> yep. husbands always do it. and they just seemed like they just zeroed in on him and were going at it 110 miles an hour and were not respectful to my brother and i about any of -- developments or anything going on. >> reporter: but detective matt carter had an ongoi investigation and he felt there was ample reason to pursue their dad. after his interview with deanna, he'd driven to the hotel that was keith's alibi. there, he uncovered a bombshell. remember keith saying to the detective he'd been at the hotel the entire night? ducking out just twice to get a drink and a snack? well, unhappily for keith's alibi, when the detective hit

play on the hotel's security video it told a vastly different story. keith is seen leaving, as he'd claimed, around 11:00pm. but -- >> i think within 15 to 30 minutes, he's gonna be returning. but that never happened. >> you're scrolling through the tape? >> going through, going through. >> and then when'd your bingo moment come up? >> he finally arrived back at the hotel six hours and 34 minutes after he had left, initially. >> reporter: gone for more than six and a half hours. was that enough time for keith to drive all the way back to his house in kentucky, commit the crime, and return? >> so what did you and your partner find, when you put a clock to it? >> driving the speed limit to and from, it would've allowed approximately 20 minutes, at least, to have committed the crime. >> is that enough time on the ground for him to do this lethal act, kill his wife and torch the house? >> believe it was ample time -- >> 15, 20-minute window? >> yes. >> reporter: keith griffith was arrested and charged with arson and murder. >> care to answer the allegations sir? >> reporter: he could face the death penalty. he pleaded not guilty.

>> we were all frantic, we had no idea what was happening, how it could have happened. because at that point, we knew that there was -- there was no way that he had anything to do with it. >> so this is nightmare country? >> yes. but again, we thought it would all be explained. you know, they would do their job, they would take him and the truth would come out. >> i was 100% convinced that he was innocent and that they were taking the wrong person in. meanwhile, the person who actually did it was getting away. >> reporter: family and friends were, for sure, distressed to learn that keith had another woman on the road but the revelation wasn't enough to shake their support for him. >> it was a shock, but it was something that we accepted as a mistake. but that did not mean that he killed julie. >> there's just no way he did it. >> yeah, this is -- >> not to julie. >> definitely. >> his wife, you know, kids' mother, there's no way keith did it. >> reporter: but when keith griffith went to trial in february 2015, prosecutor raymond mcgee laid out a formidable circumstantial case. >> because on january 17, 2014,

keith griffith decided that he could kill his wife. >> reporter: a cornerstone of the case was that hotel security video. not only did it show keith gone for enough time to commit the crime, the prosecutor said, it also caught him in a lie. remember, in his interview, keith told police he hadn't swapped clothes that night. >> not at any point changed clothes? >> no. >> reporter: but a look at the security footage showed he had. >> he left wearing one set of clothes. it was one of his work shirts. he came back dressed in all black. >> reporter: the prosecutor also showed security video captured from a residence near the griffith home. it caught a glimpse of an suv pulling into the subdivision shortly before the fire. >> it was a little blurry. it was a few seconds long. but it sure looked like keith griffith's car. >> reporter: and another circumstantial bit. who else but keith, the prosecutor said, could have gotten by the griffith's aggressive great dane cleo? certainly not an unknown intruder. >> the dog and keith were very close. but a burglar couldn't have come in. a family member could have. >> reporter: as for the why question, "how could keith, a

man who by all accounts loved his wife, actually do it?" the prosecutor turned to two age old motives. >> almost every case involving a husband and a wife, it's lust and greed. one or the other, and this one had both. >> reporter: the lust part of the equation, he said, was deanna. she took the stand and told the jury that not only was keith house hunting for them, he was also making plans to bring her down to paducah for a concert and introduce her to his family. >> i'd love for you to come for the weekend, stay for the weekend. we'll go to the concert and i would really like for you to meet my dad. >> reporter: as for the greed part, that was life insurance money, two policies on julie's life worth $250,000. one of them, the prosecutor said, had taken effect just eight days before julie died. >> keith griffith got to the point in his life he just wanted to start something new. and he didn't wanna give julie griffith what she would have needed in a divorce and been

entitled to. >> reporter: keith's daughter-in-law, ali griffith, listened to the entirety of the prosecution's case. all she heard were theories. >> they spun a story, and they told a story, how they wanted it to go. and they had facts that supported their story, but did not prove it. >> reporter: and that's what keith's defense attorney, mark bryant, hammered home for the jury. >> what's no evidence mean? >> they didn't have dna, they didn't have any kinda forensics, they didn't have a confession. they had nothing. they had circumstantial evidence. >> reporter: in their haste to arrest keith, the defense argued, the police had gotten it wildly wrong. yes, he conceded, keith wasn't the husband of the year. but, he said, deanna's story that keith was pursuing her for a long term commitment was nonsense. rather -- >> what he wanted was a port in every storm. >> reporter: as for the life insurance, $250,000 was far from a financial windfall, he said.

even the bradleys knew that the reason keith and julie bought that new policy was because of a friend's recent tragedy. >> she had been nagging them about getting -- making sure they had plenty of life insurance. >> reporter: and, he argued, the footage of the suv pulling into the subdivision was far too blurry to i.d. it as keith's ford expedition. besides -- >> if a guy is gonna go to this much trouble to kill his wife, why would he drive an expedition that everybody knows he has? >> reporter: but the big question still remained, if keith hadn't driven back to paducah to kill julie, where had he gone the night of the murder? the only person who could answer that was keith himself. >> he was very adamant about taking the stand. >> he wanted to talk to the jury? >> he did. >> reporter: what would he say? and would the jury believe him? it was roll the dice time. coming up -- keith's eyebrow raising alibi. >> i was embarrassed and ashamed of what i was doing the night my wife died. >> and then what keith revealed to us.

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>> reporter: keith griffith was about to take the stand and explain the most damning piece of evidence against him -- hotel

security footage that put him off the grid for more than six and a half hours the night his wife, julie, was murdered. but if he wasn't perpetrating the crime during that time, then where was he? >> tell us your name, please, sir. >> keith wayne griffith. >> reporter: keith's explanation came with an embarrassing secret. his lawyer argued that that ever since becoming a travelling salesman, keith struggled with an addiction to sex. >> keith, until you got out on the road several years ago, did you have this kind of a sexual addiction? >> no, sir. >> reporter: and the night julie was murdered, he said, he spent those hours out prowling for women. after he left the hotel, he changed out of work clothes into his man-out-looking duds. >> didn't like people to put my job with my carousing. >> with your carousing? >> uh-huh. >> all right. >> reporter: he says he went to a massage parlor, a bar and a couple of strip clubs, but, try

as he might, he never found a hook-up. >> i was trying to pick somebody up, and there wasn't anybody available or interested or however you want to put it. reporter: after last call, he said he went down to the river to watch the boats before returning to the hotel to catch some shut eye. as for why he lied to the police -- >> i was embarrassed and ashamed of what i was doing the night my wife died. >> did you kill your wife? >> no, sir. i did not. i loved my wife. >> did you burn that house down, keith? >> no, sir. >> did you kill those dogs? >> no. i loved those dogs. >> reporter: when the case went to the jury. keith's friend, craig bradley, didn't know which way the jury would fall. >> i didn't know if he'd get acquitted, but i didn't think he'd get convicted. i mean, i really felt like it'd be a hung jury.

>> reporter: turns out, he was right. after six hours of deliberation, the jury was deadlocked. >> i'm going to declare a mistrial at this time. >> reporter: keith would sit in jail for another year as he awaited a second trial. a long time for his family to process the story he told on the stand. >> he left to go to a bar to go cruising or something, and then he goes and sits on the riverfront? like, he has never done that before in his entire life. >> so when he stepped down, you thought "my father did this thing"? >> yeah. i mean, i definitely wasn't saying it out loud and i wasn't ready to accept it, but i definitely was moving in the direction of the only thing that makes sense at this point is that he committed the crime. >> reporter: after months of wrestling with his thoughts, zach decided it was time to send his dad a letter. >> i put in the letter, my opinion was "that you did it," you know, "you took away that -- the last chance that i had at rebuilding a relationship with my mom. you know "you're no longer allowed to contact me -- and i don't want you to ask about me to anyone." >> wow. "dear dad, you are dead to me." >> exactly. >> reporter: his brother's wife, ali, had started to feel that

way about keith too. >> it seemed like he was fabricating everything that came out of his mouth. >> reporter: but there was a split in the family. despite doubts of his own, her husband, aaron, the one closest to his father, was still a supporter. >> whatever issues my mom and dad would've had, i just could not believe that my dad would take my kids away from their nana. >> reporter: then, a few months before keith's retrial, detective carter's phone rang. there was news from the jail. an inmate had some information about keith. and it was as eerie was it was chilling. the detective in the bullseye. >> keith had come forward to him, wanting to have me killed. >> reporter: to put a hit on you? >> to put a hit on me. >> orchestrating your death? >> yes. he'd drawn a map of what he believed to be my residence, suggested the caliber of weapon to use to kill me. the informant specifically asked him -- what -- what if my family was present? and his response was one word. and that was "tragedy."

>> reporter: wow. that does make the hair on your neck stand up? >> it does. >> reporter: that wouldn't look good to a jury. the development brought aaron to a tipping point. were you no longer wavering at this point, aaron? had you come down on the side of, "oh, my god?" >> yeah. >> reporter: "my father killed my mother?" >> yeah. >> reporter: now, aaron, too, wrote his dad a letter. if he was guilty -- >> it's time. it's time to man up and -- and do what you should've done two years ago. >> reporter: keith's defense attorneys went to the prosecutors to hammer out a plea deal. they agreed on 30 years in prison for the murder and for soliciting the hit. moments later, keith was standing in a paducah courtroom, speaking the words his family and friends never in a million years thought they'd hear him say -- yes, he murdered julie. >> there's no excuse for what i did, and i can't take it back, and she was my best friend and i don't know what happened to me, but i did it, and there's nothing i can do about it. >> reporter: temple bradley, who works near the courthouse, was there.

>> i'm just -- my heart breaking. that the person that i have put -- whole heartedly put my trust in for two years has lied to my face. >> i just can't believe we've been deceived in that way, because we were there for him the whole time. >> reporter: for keith's family and friends, there are so many questions. but one seems to tower above all the others. >> i want to know why? i want to know how you go from a loving husband and father and grandfather to driving all that way, killing your wife -- and then, covering it up and then lying to your family for so long knowing that we had everybody doubting us, yet we still defended him. disgusting, he's a monster. >> all i can tell you is that -- had a lot of bad thoughts, wrong thoughts, mistakes. >> reporter: we sat down with keith hoping for answers. but as many times as we asked him why this all happened.

why'd you do it? >> i really can't tell you. i mean, i don't know. i mean, just -- just a bad decision. >> reporter: we never did get a satisfying response. so this isn't some kind of >> i really can't tell you. i mean, i don't know. i mean, just -- just a bad decision. >> reporter: we never did get a satisfying response. so this isn't some kind of delayed midlife crisis here? >> no. >> reporter: where you're trying to be with deanna or someone like her to have -- >> no. >> reporter: a final, happy chapter in your life. >> no. >> reporter: new house, new life -- >> julie and i were happy. >> reporter: do you see how perplexing it is to hear this story? >> oh, i know, i -- and i -- >> reporter: it's absolutely confounding. >> it's what i've told everybody, that when they hear the story, they're not gonna believe it. i have a hard time believing that i did what i did. >> reporter: and one thing he didn't do -- how about a divorce? >> never crossed my mind. >> reporter: keith now says the remorse began the moment he pulled out of his driveway. >> it's trying to get out of the subdivision, crying before i ever get out, regretting what i'd done. i probably drove 100 miles an

hour all the way back, hoping to get caught. >> reporter: as for the future, keith says, he is prepared to die in prison. >> i don't have anything to live for, except maybe forgiveness. >> reporter: from who? >> from my boys. >> reporter: and that's why you're talking today? >> exactly. yes. >> reporter: well, it's between you and them, but i'll -- i'll tell you, my take on it is you got some distance to make up. >> oh, i know i do, i've got a lot to make up. >> reporter: of the countless things keith stole from his family, resilience was not among them. aaron and zach are closer than they've been in years, and now that they know what happened to their mother, they say they can finally mourn her passing and focus on keeping her spirit alive for those two little granddaughters who were the center of her universe. >> my oldest daughter will remember. she talks about her almost every day. we have pictures of her up in her room. as my youngest gets older we'll

tell her the nascar nana story about how she -- when she was born and -- and just never let her memory die. that's all for now. thanks for joining us. i'm craig melvin. >> i'm natalie morales. >> and this is "dateline." never good news when the phone rings at 5:00 in the morning. i knew something wasn't right. he just began sobbing and saying no, no. >> it was just before midnight when the shooting started. >> he had been shot multiple times. he was on the ground, face down. >> a man was dead, but not just any man. >> how do you kill