and six covert actions based on those reports. in each case, a single namegets added to what i wrote, and each time,that name turns out to be the key to stoppinga major terrorist attack. six for six. the only way to be that accurate is with illegal surveillance on a massive scale. then there's this: "sibilance" is an internal audit of the nsa intranet. it's totally routine-- until they find signals hidden just beyond the shannon limit. it should just be static, but there was data. someone is sneaking just as much data out as the nsa is taking in. to scan through all that, you need an organization ten times our size. it's more than any human-- oh, my god, they actually built it. after 9/11, the government wanted a computer system-- a machine--

catch terrorists before they strike. they tried with trailblazer, t.i.a., stellar wind. they--they all failed. but if i'm right, then someone really built the damn thing, and it's watching us right now. - okay, you want a soda or something? - you just questioned my suspect? - questioned your suspect? guy's in there talkinga blue streak all by himself. should be wearing a tinfoil hat. gets arrested yesterday for drugs, tonight he throws a bottle at a cop-- this guy's out of his mind. - we need to get you out of here, henry. - who are you? [david bowie's i'm afraid of americans] - johnny's in america no tricks at the wheel - i supposewe can count our blessings

but peck's in more danger than ever. - seriously, who the hell are you? - all henry peck did was ask questions. he deserves a normal life, and if we have any hope of giving it to him, we have to destroy all that evidence and stop him from getting any more. [engine revving] - yes, my name is henry peck. i'm an analyst--- who did you just call? - the office of special counsel. it's the agencythat protects whistleblowers. - oh, i really wish you hadn'tlet him do that, mr. reese. the people who know about the machine, one of them works forthe office of special counsel. [phone clatters] - what are you doing? our own government is spying on us and they want to kill me to cover it up. i have to tell someone! - the people you calledaren't who you think they are. there's no one to tell. no one is safe. - he just called us.

- that's all i need. - johnny's in america i'm afraid of americans i'm afraid of the world [gunshot] - get down. - i'm afraid i can't help it i'm afraid i can't i'm afraid of americans i'm afraid of the words i'm afraid i can't help it i'm afraid i can't i'm afraid of americans for adults with an advanced lung cancer called "squamous non-small cell", previously treated with platinum-based chemotherapy, it's not every day something this big comes along. a chance to live longer with... opdivo, nivolumab. opdivo is the first and only immunotherapy

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bristol-myers squibb thanks the patients and physicians who participated in the opdivo clinical trial. the flu virus. it's a really big deal. and with fever, aches, and chills, mom knows it needs a big solution: an antiviral. don't kid around with the flu, call your doctor within the first 48 hours of symptoms and ask about prescription tamiflu. attack the flu virus at its source with tamiflu, an antiviral that helps stop it from spreading in the body. tamiflu in liquid form is fda approved to treat the flu in people two weeks of age and older whose flu symptoms started within the last two days. before taking tamiflu tell your doctor if you're pregnant, nursing, have serious health conditions, or take other medicines. if you develop an allergic reaction, a severe rash, or signs of unusual behavior, stop taking tamiflu and call your doctor immediately. children and adolescents in particular may be at an increased risk of seizures, confusion, or abnormal behavior. the most common side effects are mild

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[grunting] [knife slicing] - [groans] - do you know whyyou were ordered to kill him? - never asked. [sirens wailing] - okay, peck, let's get you out of-- [exhales heavily] this isn't over, finch. the man wrote 78 pagesto fight a speeding ticket. - i know. he's not gonna give up. and neither are the peoplewho know about the machine. - so what the hell are we gonna do?

even with an intractable problem, one can still find a way to do the right thing. [sighs] [mechanical chirping] [suspenseful music] [typing] - your predecessors failed, and now peck'sreaching out to the press. he's meeting a reporter tomorrow. i want you to silence them both.

[chair scraping on ground] - you're not the reporter. - no. no, i'm not. oh, she's quite safe. right now, my associate is dealing with the assassinswho were sent to kill you both. the answerto your question is yes. it exists. and it's watching us right now. i'm telling you this because you remind me a little of myself. and i know that, if i were you, i would keep asking until i knew the truth. so now you do. now stop asking the question. - where is it? how does it work?i mean, the servers alone-- - i know how you feel.

but believe me, mr. peck, this is a mysteryyou do not want to solve. knowing the answer has cost me somethingi value more than my own life. clean passport, plane tickets, a bank card to a well-fundedaccount in your new name. please, mr. peck, for your own sake--and quite frankly, for mine-- go and live your life.find some secrets of your own. and if you really need a mystery, i recommend the human heart. - how do you know all this? - because i built it.

- that guy peck who pulled the disappearing act, we just pulled his prints off a burnt-out cab with a john doe next to it. - what about peck?any idea where he is now? - he's in the wind. a bunch of paper burned up in that cab. all we could make out was this. [phone rings] - hey, this h.r. deal's a lock. we get three days to prepare. now we gonna do this or not? - we'll be ready. i'll call you as soon as i'm done here. - yeah, right. like you'll ever be done spying on mr. glasses. - next time i see you,i just might have his address.

- and you're here every day? hello, finch. - can i help you? - sorry to bother you. detective stills. someone reporteda disturbance at this address. - really? i'm the only one here. - probably just an old lady who saw a shadow or a kid playing a joke. we just haveto check everything out. do you want help with these?

- there must be about 50 copies here. you a collector? - uh, kind of. they send me extras when it's one of mine. - you draw the covers. - yeah.a bit old-fashioned, i know. everything's going digital. print is dying. but, uh, every time i think i'll never work again, another magazineor newspaper calls, so... guess i have a guardian angel. - who's this? - um, that's harold, my fiance. - looks like a nice guy. - yeah. he's a very nice guy. i never really thoughtthat i'd meet anyone who got me. you know, spending allyour time alone, drawing, isn't exactlythe best way to find someone. [chuckles] but harold found me.

and...there was this man, eating an ice cream cone in january. and he smiled at me. he asked me if i wanted one. - does he live here with you? - no, he doesn't. um, he used to. i lost him two years ago. there was an accident. - i'm sorry. good location.

but enough obstructions and distance to avoid being seen. - i built an app that alerts me if i ever getwithin 100 meters of her. i've never regretted building the machine. but i didn't fully realize the personal cost. i'm good with computers. people--well,people other than grace-- have always been a mystery to me. i failed to recognize the lengths to which they wouldgo to protect the machine, to control it. by the time i realized it, it was too late... for me. but not for her. you see, mr. reese, if knowing about the machine is like a virus, that makes me patient zero.

- i'm sorry. - i was lucky. i had four years of... happiness. some people only get four days. please, mr. peck, for your own sake-- and quite frankly, for mine-- go live your life. find some secrets of your own. - god is an american

i recommend the human heart. - how do you know all this? - god is an american - because i built it. - god is an american

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i'm getting ready to leave the house, and the phone rings, you could see the area where heidi was.

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 doughswindows, door nothing was 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

>> 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 ay 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

>> 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 there, you know that's not good. >> it was a murder case that wasn't going to be solved in a few hours or a woo-woo weeks or even 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.

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.

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 lding 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.

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. 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

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?

>> and a possible suspect. >> i'm thinking maybe this is our guy. heidi's killed with a knife. holy night sleep in heavenly peace

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it's what you do. you make me feel so spring has sprung. >> 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,

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

>> 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

>> 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

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 ali.bi 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

>> 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 nftna was found under heidi's 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

>> 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.

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 suspect suspect. who it was shocked everyone.

it's alway >> 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.

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

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. anything in heidi's circle, alexander bennett from colorado? >> 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

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 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' >> so it's not all muffled or disguised or -- >> no. no, it's just -- >> -- that's grant lewis, i know him. >> yes. >> reporter: within days, lewis

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

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

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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-h. i'm gary childs. how you doing? >> reporter: at first, the deteive kept ivague, tryin conrm that bennett had inde beein balmore at the timef the muer, e year000. bennt said he was. he snt about a mth othe stets the,ftereing ditcheby se frnds their wato aonce.

strae. >> tt's y -- it strge. >> reastrae. and en not to memb anybody you ayed witor hked with. >> rorter: the the decti playedis han laidut the rean for his sit. >> thigirl fingernai wer taken the time of hereath. and unr her ngernailis your dna. now thers no denyingt. >>eporter: but bentt did have an explanion. and itad nothing to doith committing murder in a house. >>e remembers a confrontation thate 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, aechnique police typically use to help identify criminals. except this time, he was asking

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

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 >> 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

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 hay. 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

then came the morning of jury lection. >> gary d i e out gettin breakfast. and gary phone gs of d he loo down it. looks uat m and 's like,lewantto talk. ani'm, like,ow. heree go >>eporter: a heart-to-hear 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

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.

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