[music playing] i'm often asked how the classical progression style works. well, here we are, at the heart of it all. this main space of our home is a modern-feeling, high-ceiling space, but yet, it's built with all of these wonderful antiques and recycled materials. part of the greet room is this formal dining area. this table top is actually a piece of hardwood flooring from amsterdam. there is a church pew that we use instead of chairs on one side of the table. and we needed a china cabinet for all of our storage. so we found this old bookshelf, put wrought ion doors on it, and there's lots of storage here for everything. and here we are, in the master suite. while the anteroom is more of a traditional feature, the angled walls of this bedroom are much more modern.

they're a result of the curved and angled front facade. we chose an antique fireplace mantle from bourbon street in new orleans and set it on to a very simple clean glass shelf wall, which creates depth and interest. for the master bath, we chose a graphic black-and-white marble floor and installed this beautiful claw-foot bathtub-- reminiscent of the french hotel suites we so adored. [music fading] [music playing] you always hear about california outdoor living. well, we truly live it. i love to cook and entertain and kevin loves to be outside, so we created an extension of our indoor living space, which is comfortable, functional, and inspired by the beautiful lush surroundings. a petting zoo, vegetable garden, and aviary complete the package. and that's it. it's been a pleasure sharing our home with you.

thanks for joining. [music playing] now, if you've found creative ways to reuse and recycle when it comes to home decor, tell us about it on twitter, instagram, or facebook @openhousetv. still ahead, we asked a group of kiddos what home means to them. hear what they have to say coming up. [music playing]

welcome back. no place has a better story than home. our homes play an important role in the storybook of our lives. it's a message that hits home for our partners, coldwell banker. throughout the year, they've asked buyers and sellers to share their stories. so what does home mean to you? we decided to pose that very question to kids. we headed to compass charter school in fort greene's section of brooklyn to find out what home means to the little ones. i'm ashley dembowski, vice president of operations, coldwell banker real estate. at this time of year, we are reminded of all the wonderful reasons that we are so thankful for home. at coldwell banker, we believe it is not just a roof over our head, that home represents everything we hold dear. and often, it's kids that have the unique perspective of what makes home so special. [music playing]

[scribbling] [music playing] my favorite thing about home is that i get to sleep in my bed with my cozy animals. my favorite thing about home is there's two floors in my house. and also, i get a backyard. i can see my mommy, my daddy, and also my grandma. i have four chickens. what? and a dog and a cat. i have like five cats. five cats? whoa. when i go to sleep, my cat always comes in and just climbs up my shirt every night. [scribbling] [music playing] at home, i like to play games with my brothers and my sister. and sometimes, when we play games with my brother, we actually make it a deal so whoever wins the game, they get to have what we were fighting over. when i'm home, i like to do-- i like to-- i

like to cuddle up and play with my sister. i like to play the word games with her, like junior monopoly. my favorite thing at home is sleeping with my mommy. my favorite thing to do at home is to lie on my mom legs and hold one of my toys while watching tv. ooh. [scribbling] [music playing] my home is brown, and it's big. and i have a basement. my house is brown, and it-- my elevator door used to be black, but now, it's white. i live in an apartment building. the shoe hallway is like almost the whole entire house. [scribbling] [music playing] my favorite place is my bedroom because i can bounce on the bed

all the time. my favorite place at home is my backyard because i can get out my house quickly and go out and play. my favorite place is the living room. if my mom isn't here, i use my favorite pillow. [scribbling] [music playing] i'm thankful that i get to have play dates with my friends and that i get to have love with my family. at bedtime, we always get to have a little time together. that we at least have a school and we have shelter from rain. [music playing] [scribbling] [music playing] [music playing]

[music playing] i'm thankful for home! no matter how old we grow, one thing always rings true-- there's no place like home. for 109 years, coldwell banker has been helping people find home. to find a home of your own, visit coldwellbanker.com. that is too cute. to share your stories of home, head to coldwellbanker.com. up next, we are heading to a magnificent waterfront estate in connecticut. and later, diy design tips that you can seriously do yourself. trust me. [music playing] open house is brought to you in part by coldwell banker-- where home begins. [music fading]

welcome back. now, we're heading to darien, connecticut. we're stopping by a magnificent waterfront estate with lush gardens and sweeping lawns. this home features nearly 15,000 square feet of exquisite detail. you'll be impressed from the moment you enter the stunning entry hall. [music playing] hi. i'm brooke. and i'm courtney. and this is our family's home at 188 long neck point road in darien, connecticut. let's head inside. [music playing] as you come into the foyer, you see 22-foot ceilings, floor-to-ceiling windows, and incredible view of long island sound. one of the interesting things about this room, it was originally four separate rooms and we've opened it up to make this incredible entertaining space. we have a beautiful elliptical staircase that we imported from france, and we have beautiful details throughout the house that were handcrafted in europe as well. [music playing]

one of our favorite things about the library is to come in here after the party's over and kick back with a glass of wine, our entire family, and talk about the night's events. one of the original details of the house is this incredible mahogany hand-crafted fireplace, and on the other side of the library is the walk-in wine cellar. [music playing] just off the living room is the dining room. some of my favorite features of this room are the egg and dart moldings and the elegant architectural details. they make you feel like you're dining in a different era. [music playing] while this room is technically our kitchen, it actually functions more as a family room. we have coffee over here in the morning, informal dining, and at night, we cuddle up and watch tv. we truly use every inch of this room. [music playing] this is such a regal master suite. you enter in through this huge sitting room with venetian plaster walls and a marble fireplace. and a terrace. what more can you ask for in a master bedroom? [music playing]

and finally, the outdoor space. why would you go anyplace else? done al fresco or have a big party on the vast lawn, there are manicured gardens, access to the beach, and a pier to pull up your boat. even on cloudy day, this home is a serene oasis. [music playing] thank you for joining us today. we've had so many incredible memories here. we hope you enjoyed this tour of our family's home. [music playing] there is still more ahead. next, tips to help you bring a designer touch to your kid's room. i'm going to show you a simple trick that will give this basic dresser a much-needed and more stylish second life. [music playing]

welcome back. when it comes to decorating, there's nothing more fun than designing a kid's room. and with a little creativity, you can save money and time by doing it yourself. expert stager cheryl eisen is here with some diy tips that will upgrade your child's room in a flash. [music playing] hi. i'm cheryl eisen of interior marketing group.

today, i'm coming to you from 1110 park avenue-- a new development by toll brothers city living-- where i'm going to show you some fun and functional things you can do to take your kid's room design to the next level, breathing new life into ordinary things you may already have around the house. [music playing] any city dweller knows storage space is always at a premium, especially in kid's rooms. using only a few l brackets, we've repurposed these cool skateboards into functional shelving. it's not just a stash for toys. it stores the boards, too. [music playing] campaign dressers are such a classic look for the home. i'm going to show you a simple trick that will give this basic dresser a much-needed and more stylish second life. this campaign hardware you can buy at any local hardware store. all you need from there is a drill, and you're ready to go.

[music playing] kids love animals, and i'm going to show you how to do your own zoo-inspired art gallery. all you'll need for this project are some store-bought frames in varying sizes, sharpie pens, a pair of scissors, some glue stick, newspaper, and pictures of animal prints you can find anywhere online. so to start off, just take the print of your animal and start to trace it wit your sharpie. the next step is to just take the print and cut out what you've traced. [music playing] piece of cake. now that you have your perfect silhouette, just color it in with a big fat marker. [music playing] there you have it. now that you have your animal silhouette, just find a newspaper with as much print as possible. cut it out. position the art. glue it down, and place the art in the frame.

[music playing] now, just close it up, and we're on our way to the zoo. [music playing] the beauty of these tricks i've shown you today is that they put the fun in functionality, so get the whole family in on a diy day. i know you'll be pleased with the results. [music fading] [music playing] for more diy inspiration, find us on pinterest or facebook. and while you're on facebook, be sure to check out my breakfast with open house videos every weekend and share what you're having with us. each week, i whip up one of my favorite family-friendly recipes. be sure to like the video, share it, and comment for a chance to choose the next recipe i'll make. that's all for now, and thanks for watching. we're back next week with more beautiful homes. [music playing]

i'm getting ready to leave the house, and the phone rings, you could see the area where heidi was. i was lost for words. just doesn't make sense.

>> a vibrant young woman stalked by a killer. >> i cringe every tomb i think about it. >> found dead by her boyfriend. >> my brother was a mess. was devastated. >> the most ominous clue -- >> on the wall to the left where heidi's body was, was a number one, she's number one, get ready. >> right. >> here comes trouble? >> exactly. >> it wasn't a break-in. the one dougwindows, door nothi broken. did the killer have a key? >> the question was, how did the person get into the house? >> a decade later, in a state 1500 miles awaying detectives finally found their answer. >> got dna hit. >> and more questions. >> we knew there was more to this story than some guy comes from colorado to commit a murder and go back home again. >> did someone closer to home want her dead? >> you're 99% sure that he had something to do with it, but there's no smoking gun.

>> so many secrets still be revealed. >> and one more killer on the run. >> he knew what was in the house. he knew what he was doing. done get any where's than that there i'm lester holt and this is "dateline." here's dennis murphy with "indiscretion." >> she was bubbly woman in her early 20s, just looking for a clean break. heidi, a baltimore pool league ace, had, in recent years, endured tough times but now shots were starting to drop. a steady job as a receptionist, a boyfriend she could take to meet the parents, talk even of a summer wedding in las vegas. and then, it was game over for heidi. just like that. someone had made their way into her row house on a thursday night in april back in the year 2000, and killed her most brutal

fashion. >> 911. >> my girlfriend's been murdered. >> what happened? was she shot? >> just -- she's cut. her throat's cut. >> any parent opens the door, 6:00 a.m., two cops standing at's n you know th few hours or a w-w weeksen a dozen years. the heidi murder investigation would go stone cold until one day, in a matter of hours really, everything became clear and how strange and terrifying it all turned out to be. when donna and walter met at a church soesh talk of a family even preceded the engagement ring. >> he used to scare the girls away by saying he wanted 12 children, i said, i always thought i wanted to have 12 children. he said, oh my god. >> they didn't have 12. but this devout roman catholic couple did raise their five in a baltimore, maryland suburb.

heidi, the only girl in a sea of brothers. >> when i hear that, i think, poor heidi. >> yep. >> growing up with boys. >> we had friends that said, she must have been treated like a princess. i said, are you kidding me? she had to have been cuff as they were. >> kept them in their place. >> she wasn't treated like she was a princess, that's for sure. >> heidi grew up to be happy, athletic, healthy girlfriended by friend mz a noisy, loving family with strict rules. everyone at table for dinner, mass on sunday, no back talk. heidi's brothers, frank and harold, true your moms and known to wash out a naughty mouth with a bar of soap. >> i got it. >> true? >> they were very strict. definitely had a bar of soap from time to time. >> as she grew into her late teens, heidi starts to bristle under her parents' strict house rules. by 19, she, the next to

youngest, became the first to leave the family nest. but the grass wasn't greener. right away, reality offered up a deadbeat roommate, and a succession of low-paying jobs that evaporated like the morning dew. yet she could count on girlfriends to buoy her up, one night with her bffs shooting pool she caught the eye of a guy holding a cue stick, steven cook. >> shooting against one another and he noticed heidi in the bar. >> steven cook's sister. >> the first night he went home and three days later they moved in. >> really fast. >> steven was five years older than heidi. his sister says he could be quiet and shy, but always wanted to be around heidi. >> they did everything together. i don't think that they really did much without each other. >> in 1998, steven and heidi

moved to the rental townhouse in maryland. steven's dad, steve sr., says, after living together for nearly two years, the couple was talking about taking the next step. >> it was your understanding, steve, they were going to get hitched? >> yes, in vegas. every time i talked to them that was their planned. it never changed. he loved her. >> timing seemed good. heidi just gotten a promotion at insurance company where she worked. she was fine 4 a 9:00 to 5:00er after years of tempt teching. >> she was getting started when things happened. >> strange things that ratted heidi. in april that year, someone was trying to break into their townhouse. there was chipping around a lock on their basement door. >> looked like the doors had been monkeyed with. >> yes. >> not on after that discovery of mischief on the locks a stranger knocked on the front door, saying he was forming a neighborhood block watch. he scared heidi so much, she

told her friends, described the person as african-american with a tattoo. steven demanded new locks and keys from townhouse management. they were installed april 19, 2000. the next evening is when it happened. >> you sending somebody? >> yes, i am. >> just send somebody. >> stay with me, okay. >> an officer dispatched to their home saw heidi on the living room floor. her boyfriend leaned up against the wall, cradling her and crying uncontrollably. it appeared she had been strangled, her throat so severely slashed her blood dripped through to the basement. and there was something else, something mansenesque, scrolled on the wall in red lipstick above heidi's body was the number one. >> when we come back was a killer keeping track of victims. >> she's number one, get ready, here comes trouble? >> exactly. >> and a possible suspect. >> i'm thinking maybe this is our guy.

heidi's killed with a knife. ♪ holy night ♪ sleep in heavenly peace ♪ sleep in heavenly peace

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>> reporter: a remail police officer was the first on the awful scene. >> she's seeing steven cook holding heidi up against the wall, the wrapping -- he's got her wrapped in his arms. >> reporter: steven cook, heidi's live-in boyfriend of nearly two years, told the arriving officer that he came home that night only to find an apparently lifeless heidi in

their living room. nonetheless, he says he tried cpr. 8:58 p.m., he called 911. >> are you sending somebody? >> yes, they're on the way, sir. i want you to stay with me. >> no, no, i can stay with you. i've got to go with her. >> reporter: baltimore county homicide detectives al and gary arrived later that night. it appeared to them, heidi had been strangled, it was obvious her throat had been deeply cut with something sharp-edged, probably a nigh. when you go to that scene, does it speak to you, explain itself what happened here? >> it was kind of an odd scene. in the living room of the house, there was no real furniture, to speak of. up on the wall to left of where heidi's body was, was a number one, written on the wall. so found that obviously to be odd. >> reporter: she's number one and get ready because here comes trouble? >> exactly. >> reporter: those first few

hours left investigators wondering, was this the first signature of a budding serial killer, was there going to be a number two, or was it something else? >> the house was tossed, you know, ransacked. you've got a potential motive of burglary and you've got the other motive on the wall of serial murder. >> reporter: 20 miles away, walter and donna got a knock on the door at their maryland hole, it was the police. >> they says you have a daughter, heidi. yes. you know, and i said, you know, what's the matter? you know, she's been in an accident? what's going on? he said, heidi's dead. >> it -- you know, quite a shock. i started pinching myself, got to wake up from this dream, this has got to be a dream. >> i think our whole world changed. >> reporter: a short time late, steven's sister kim got a knock, too. >> i remember running to the bathroom and getting sick and i

was kind of -- i couldn't -- i couldn't do anything. >> reporter: heidi's boyfriend, steven, meanwhile, had been down at a police station the whole time being interviewed. officers snapped this picture, his clothes bloodied, he said, trying to perform cpr, and then cradling heidi's bleeding body. how much did you know about him or the victim at that point? >> not a lot. we knew they were in a relationship, the relationship was good. >> reporter: husbands and boyfriends are always persons of interest. but homicide investigators say, steven was cooperative. he told them how, after his shift ended at a local lowe's, he pickeded up heidi from her job and the car they shared, 1994, red honda civic. it was 5:45 p.m. when he dropped her off at their home. it was, he said, the last time he saw her alive. the detectives put together a time line for the boyfriend, who run a bunch of errands after dropping heidi off. a stop at the atm, followed but

a haircut, oil change at a jiffy lube, and then a swing by home depot, for a plumbing piece needed to repair his sister's sink that night. he had time stamp receipted for ver actually everything, and turned them over to the police. he's got a very solid alibi for his whereabouts. >> he does. it doesn't take long to do what had been done. you know, she's strangled and her throat is slit. you know, that could happen in a matter of seconds. >> reporter: after about six hours of police questioning, steven went home. his sister remembers him being a wreck. >> i could certainly tell my brother was just a mess. he was devastated. i could see in his face that he was, just looking at him, he had been crying. >> reporter: in the days that followed, al meyer and other investigators felt a serial killer unlikely. the robbery gone bad theory,

too, no signs of a forced entry. but d nna was found under heidi fingernails, presumably from her killer. it was dashed when the sample turned out to be virtually useless. >> mixture of dan from the victim and from the suspect and technology, you couldn't separate it. >> reporter: but detective meyer did have one suspect he was very interested in finding. that suspicious neighborhood block watch person, the dark-skinned man with a tattoo who had scared heidi at her front door. one person of interest was a local butcher. terry gilliam worked with steven's sister the a safeway miles from heidi's house. >> i'm think, okay, he's african-american. i'm thinking maybe, this is our guy, butcher, heidi's killed with a knife. >> reporter: investigators theorized a connect through steven's sister. they're looking for somebody that comes to the door.

did you ever go to heidi's door and knock on the door, saying you're from the block watch association. >> actually. i department know where heidi lived at, no, never knocked on her door. >> reporter: the cops wouldn't accept the ump abouter's denials and be done. other reasons to dig deeper, including irregularity on a time card. a time changed on one specific day. it's the day of the murder, one of the times handwritten in. >> reporter: the only day of the month, everything else machines. >> have him not being able to account for himself, the day of the murder. >> reporter: and there was something else, heidi herself had said the suspicious block watch person had a tattoo on his left arm. you have a tattoo on your arm? >> yes, i do. >> reporter: left arm in. >> yes. >> terry, let me ask you, did you kill heidi? >> definitely not. >> reporter: officials weren't done yet with the butcher. and heidi's boy trend, steven cook, remained a suspect, too, despite his receipt-heavy alibi.

>> a lot of time starts to go by, doesn't it in. >> too much. >> reporter: at first, months go by. then years. more than a decade, no arrests. but there would be one advantage to the passage of time. breakthroughs in dna technology, and it finally gave police a suspe suspect. who it was shocked everyone. coming up -- it's always the husband or the boyfriend, right? but that didn't seem to be where this investigation was going. >> the headline here is steven cook is not the guy? >>

>> reporter: as the years rolled by, the heidi bernadzikowski murder case got colder and colder. detective al meyer was frustrated. he was promoted out of homicide but he never forgot the case. >> even when he was in another unit, he would come back up to the homicide unit and go through the file. >> never got squirreled away, huh? >> no, no. never. >> yeah, he never -- he never let it go.

>> reporter: heidi's grieving family was trying to get on with their lives, remembering her on her birthday by eating her favorite shrimp alfredo, but family events were hardly the same. >> you couldn't fully enjoy these special occasions because you're always painfully aware that -- >> reporter: you had an empty chair. >> you got an empty chair, that she should be there and she's not there. >> reporter: heidi's boyfriend stephen cooke was trying to move on with his life as well. he married, had a child, and landed a steady job with veterans affairs. >> reporter: he's got a normal life for the first time in a long while, huh? >> he does. things are looking pretty good for him. >> reporter: then, in 2011, 11 years after heidi's murder, meyer rejoined the homicide unit and, once again, cracked the file. this time, he and veteran baltimore county detective gary childs got an idea. >> dna technology had progressed, and we knew now that there's a possibility that heidi's

fingernails may contain some physical evidence. >> reporter: so what's the thought, let's run it again, see what happens? >> yeah. the thought was to resubmit. >> reporter: to their surprise, the criminal database spit out a match. >> we got a dna hit. i couldn't believe it. >> reporter: but the hit wasn't for anyone in heidi's known circle, even in her geography. it was a name completely off the radar from a state over 1,500 miles away. >> they tell me it's this guy, alexander bennett, from colorado. >> reporter: colorado? >> and i'm, like, wow, that's not good. i'm hoping it's going to be somebody from baltimore, somebody that would be local. >> reporter: did that name mean anything in heidi's circle, alexander bennett from colorado? >> never heard of him before. >> absolutely not. >> no. >> reporter: baffled detectives started the dig. they called the colorado authorities and learned bennett was an unlikely suspected killer. in his early years, he showed promise as an opera singer. ♪

performing recitals and winning a scholarship to the prestigious manhattan school of music. after moving back to colorado though, he'd gotten into some small-time trouble. but then he did something just plain crazy. >> he's a pretty talented guy, but he had some issues with the people he hung with and one of these issues was with a friend named grant lewis. >> reporter: in 2003, bennett and grant lewis had been arrested in a doozy of a scheme. they'd called 911 and said that a friend of bennett's wanted to bomb the courthouse. but they went further, building a real bomb and planting it in his house. the bomb squad was dispatched, and that friend hauled down to the station for an interview. >> they're grilling him pretty hard because that's kind of a serious crime. one of the detectives ultimately lets him listen to the 911 call and he recognizes grant lewis' voice. >> so it's not all muffled or disguised or -- >> no. no, it's just -- >> he said, that's -- >> -- that's grant lewis, i know

him. >> yes. >> reporter: within days, lewis and bennett confessed to the whole thing. building the bomb, breaking into the house, even uploading bomb-related materials to the buddy's computer to ensure he'd be arrested. also that friend who bennett said beat him up wouldn't notice that they'd made off with his jeep. >> reporter: so it's all a hoax, this elaborate caper to plant an explosive device in order to get him out of the house so they can steal the car? >> yes. >> reporter: my word is hairbrained. what's yours? >> yeah. double harebrained. >> reporter: alexander bennett was sent to prison and required to give dna. now, years later, that dna was tying him to heidi's murder back east in maryland. for baltimore prosecutors garrett glennon and matt garrett glennon and matt breaut, the dna was an enticing lead but far from definitive proof. >> it was enough to say it looks like it came from him, you know? but we can't say it's definitively his. so there was more investigation to do.

>> reporter: so, the detectives went to work, looking for another connection between colorado native alexander bennett and the maryland murder. all the usual computer searches failed, but when sergeant meyer had the maryland state police mine an offline database -- >> i get this phone call from the trooper and he tells me, i've got alexander bennett, somebody running a wanted check on him march 30th of 2000. >> reporter: a maryland officer? >> in maryland. i'm thinking, holy cow. >> reporter: three weeks before heidi's murder, an officer had spotted alexander bennett walking down a baltimore highway. >> when a wanted check is run by a patrolman or an officer, that check remains in the computer forever. >> reporter: how important was that? >> incredibly important. >> reporter: detectives meyer and childs hopped a flight to denver. it was time to meet this alexander bennett. coming up -- >> a suspect's story, a surprise to even these experienced detectives.

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in january 2012, two baltimore county detectives flew to denver, colorado. their mission -- to track down alexander bennett, the man whose dna had been tied to heidi bernadzikowski's murder 11 years after the fact. >> dna is a good piece of evidence, but we want to find out if alexander bennett is really a part of this. >> reporter: a day after their plane was wheels down, detective childs was face-to-face with their target. >> alexander, right? >> uh-huh. >> i'm gary childs. how you doing? >> reporter: at first, the detective kept it vague, trying to confirm that bennett had indeed been in baltimore at the time of the murder, the year 2000. bennett said he was.

he'd spent about a month on the streets there, after being ditched by some friends on their way to a concert. >> i gotta tell you that's strange. >> that's why -- it is strange. >> real strange. and then not to remember anybody you stayed with or hooked up with. >> reporter: then, the detective played his hand. laid out the reason for his visit. >> this girl's fingernails were taken at the time of her death. and under her fingernails is your dna. now there's no denying it. >> reporter: but bennett did have an explanation. and it had nothing to do with committing murder in a house. >> he remembers a confrontation that he had in a bus stop with a female in maryland, in baltimore, right around the time of the murder. >> i got kinda scared because, um, you know, i was trying to fight back and i think i hurt her. i'm not sure. >> reporter: the detective didn't buy it. and thought he'd use bennett's story to his advantage. he presented bennett with several photographs, a technique police typically use to help

identify criminals. except this time, he was asking a potential killer to identify his victim. could bennett pick out the girl from his supposed fight? heidi's picture was included. >> he knows that he can't give this explanation about having this fight in the bus stop and pick some other girl. so our belief is that, if we show him these pictures, that he will pick her. and he does. >> it also, too, kind of looks like her. >> reporter: there was one more crucial detail. remember the neighborhood block watch guy who frightened heidi? the one with the distinctive tattoo? >> do you have any tattoos on your left arm? >> yeah. >> can i see it? >> when i saw the tattoo on his arm and he picked heidi's picture out, i knew it was him. >> reporter: he was the block watch guy? >> he was the block watch guy. >> reporter: but they didn't have enough evidence to book him. so they decided to call in bennett's buddy from that crazy bomb plot, grant lewis, to see what he knew. and lewis was nervous. >> sorry if i'm shaking.

i was kind of shaken up. >> reporter: he was evasive about his friend's time in baltimore, but the detective didn't buy his story. then, because lewis had an outstanding warrant, the colorado authorities arrested him. the next day, detective childs kept pressing. >> i think you don't want to tell me certain things because you don't want to hurt a friend of yours. but what i'm trying to explain to you is nothing you say hurts him is because what's done is done. >> reporter: at last, grant lewis cracked. he divulged a drunken conversation the two had down by a river after bennett got back. >> he said, i hurt someone bad. and i looked over at him and i said, i don't want to know. and he said, i think someone's dead. i think that's how he said it. i think someone's dead. and then he said, i knifed someone. >> reporter: that was it. corroboration. 12 years after heidi's murder, alexander bennett was charged. he was extradited to maryland to stand trial. heidi's brother frank got the news from their dad.

>> it was another one of those things that just brings you to tears just because all that comes flooding back in. it's such a great feeling to feel like finally something's happened. >> reporter: stephen cooke's family was relieved as well. there'd been such a cloud of suspicion around him for so long that news that someone else had been arrested for his girlfriend's murder felt like vindication. >> i was just gosh, i was ecstatic. i was, wow, this is great. >> reporter: this is relief. >> yes. >> reporter: this is what we've been -- >> finally. >> reporter: -- saying for years. it's not stephen cooke. >> i was so excited for my brother. i was just so happy. he can finally put this behind him. >> reporter: two years later, in march 2014, both stephen and heidi's families converged on the baltimore county courthouse for the start of alexander bennett's trial. grant lewis was headed there, too. he'd been flown in to testify. he's going to be your star witness. >> he absolutely. >> reporter: but for detectives, the idea that bennett killed heidi all on his own had never made sense.

they held out hope that bennett would come clean, but he maintained his innocence. then came the morning of jury selection. >> gary and i are out getting breakfast. and gary's phone goes off. and he looks down at it. he looks up at me. and he's like, alex wants to talk. and i'm, like, wow. here we go. >> reporter: a heart-to-heart with his mother had convinced bennett to spill everything. prosecutor garret glennon. >> she basically told alexander if he did this, it was time to come clean, that jesus would forgive him. >> reporter: what they call a come to jesus moment was what -- >> it appeared that way. >> reporter: you were beneficiaries of, huh? >> it appeared that way. >> reporter: bennett confessed that he killed heidi. but he hadn't acted alone, he said. he had an accomplice. and that person was, who else, but the state's star witness. >> he and grant lewis, as in the bomb scheme, had developed an idea of being contract murderers. >> reporter: grant lewis is the brains of this operation?

>> yeah. it was a lag of brains. >> reporter: grant lewis had been sitting in a hotel room preparing to testify. now detectives brought him in and turned the tables on him. >> grant, you're in the middle of this thing. >> i am not in the middle of this thing. >> reporter: at first, lewis denied involvement, but as the detective revealed details from alexander's confession, he started to open up. >> did you send him to baltimore? >> i didn't send him to baltimore, but i know more about this than i've said. >> reporter: lewis ultimately admitted to being involved in a murder for hire scam, but said bennett was never supposed to kill anyone. only to get the upfront money before turning the person who hired them over to the fbi. did you believe that story? >> not in the least. >> reporter: so now do you read grant lewis his rights? >> yes. and the cuffs went on. >> reporter: but there was still one major detail left -- who hired them to kill heidi? coming up -- >> reporter: what really happened the day heidi died? a first-person account from the killers.

>> i was making sure that she was alive. i didn't know. this sunday morning, the terror attacks in san bernardino. did the killers get help? why did no one see this coming? and can we prevent these kinds of attacks from happening here in the united states? we'll get the latest on the investigation from the very top. attorn attorney general loretta lynch joins us. plus, the role of islam, are we dealing with a perversion of the religion or a strain of it? also, the error attacks and the campaign. do these help donald trump pull away from the pack. >> every time there's a tragedy my numbers go way up. joining me are rich lowry of