>> life seem a little more precious now? >> uh-huh. >> he's encouraging us to do a lot of things. and i think he's still pushing us. >> that's all for this edition of "dateline." i'm craig melvin. thank you for watching. ♪ >> i'm craig melvin. >> and i'm natalie morales. >> and this is "dateline." >> one woman, two men. her husband, the air force captain, and the staff sergeant, her rendezvous man. >> he was a playboy himself. >> one man too much. then suddenly, there was within man less. >> it wasn't like, bang, bang, bang, bang. it was bang, pause, bang, pause. >> which sounds like what, execution? >> you could take it that way,

yes. >> reporter: a cold blooded kidding? did she? >> she was a brilliant, cunning, ruthless woman. ♪ >> hello and welcome to "dateline." the story you're about to see centers on the death of a military man thousands of miles from a battlefield, a dedicated officer who survived war zones only to be caught in the cross fire of a lover's triangle. here is keith morrison. ♪ >> what was she thinking when she went to the computer, when she typed in those five little words? did she not understand where those little words might lead? >> i need an ambulance. >> where are you at?

>> i don't know. >> what's your name? >> i'm michelle. >> michelle was, no doubt about it, dissatisfied. here she was young, successful, attractive, and yet it wasn't exactly boredom that was eating at michelle. after all, she was just starting a new career as a psychologist, often counseling troubled couples. >> she was relatively new with her license. i think that was her first real job. >> of course, michelle would have laughed at the idea that pretty soon now events would propel her to such notoriety that newspaper reporters like me lips au st lips -- my lie lizza stod ard d >> she got her degree and became a professional. >> then michelle even at an

early age seemed confident about getting what she wanted. she was 16 when she started dating marty. marty was a couple of years older, worldly, bright, friendly. he had a big plans. he wanted to be an astronaut. he went to the air force academy. she was 20 when she married him at the academy's famous chapel outside colorado springs. >> marty, you may kiss your bride. >> this was back in 1991 when marty was all she ever wanted. long before she talked to that psychologist, agreed to record for the record her thoughts about the weird events yet to come and those happy days with marty too, of course -- >> we did everything together. he treated me really well. i thought we had the perfect relationship. we were best friends. >> he was the dashing young officer back then. she, his lovely bride.

the future she imagined an endless honeymoon in which marpty's air force career would take them to exotic destinations all around the world. she just didn't imagine that world would be unromantic air force out pops posts in oklahoma, alabama and florida and finally fayetteville, income n. they came in 1999. he was captain fear by then, flew one of the huge c-130 cargo planes. all of that time alone, not so easy on a marriage, as she revealed during the tape recorded interviews with psychologist dr. debbie leighton hall. >> michelle talked about a few problems in the marriage, primary growing apart over the years. marty was away for extended periods of time. it was getting difficult for her. she was lonely. >> sometimes he was gone for months, and when he finally did come home, military families

have come to know that adjustment period all too well. they bickered, they argued about her housekeeping, his job, about having children. he wanted them, she didn't. she was worried she would be stuck raising them by herself in a town where she was already miserable and lonely. >> here i was in fayetteville, loserville, and had nobody to hang out with, nobody i could pick up the phone and call. >> that actually is about the time it started. harmless really, just a few key strokes, see what might happen. it goes on all the time these days on the internet. sexy br sexy brunette seeks rend vow man. before long her internet inquiry got a response, from him. his name was john, john diamond. >> john loved women. john was a lady's man. john always had girlfriends. >> so debbie, john's kid sister,

could certainly see her brother responding to a solicitation like michelle's. >> my brother's got a great personality. he's an attractive guy and, you know, his personality makes him that much more attractive. >> then a few days after meeting online, they met in person at a local restaurant. >> he was charming, he was funny. talked about movies and music and things we might even talk about. >> john diamond was an army staff sergeant based at fort bragg and trained as a sniper, highly regarded, decorated. had been in the service since he was 18. >> by all accounts he was a good soldier, but he was a playboy himself. he had been married once before and had a child from his first marriage and he left the first wife and married and they had a son together. >> michelle didn't know that john was still married, but maybe it didn't matter, at least not then. she loved the sex, the attention, the excitement. >> he seemed very attentive.

he was very affectionate. he was very adoring. yeah, it felt right. >> what made her so desirable to him? >> i think it was just the sex. that's what he was obsessed with. he was smitten with having sex with her. >> for michelle, well, it was more lust than love. >> she felt that the affair did not take away from the fact that she loved marty. she said he was the love of her life and that she never loved john diamond. >> and marty? >> he was in the dark, of course. when michelle told him their marriage was in crisis and they needed to see a counsellor -- >> he wouldn't agree to counseling and i moved out. he was shocked. >> michelle got her own place and spent much of that steamy fayetteville summer with john diamond. >> he was so attentive. he would rub my feet for five hours if i wanted him to. >> diamond was apparently nuts about michelle, never met anyone like her before. >> she challenged him in ways he

had never been challenged before. >> paul wool ver ton is a reporter with the "fayetteville observer." >> she was strong and intelligent and exciting for him. >> but was he enough for her? apparently not because after three months on her own michelle went back to marty. >> she felt that the marriage could survive, despite everything that had happened, that they could make it. >> so john and michelle's six month affair seemed to be off. but then a few weeks later it was apparently back on. the two traveled to the tropical island of saba where michelle interviewed for a job at a local university, and later that fall a romantic rendezvous at a raleigh hotel where they celebrated michelle's 30th birthday. but michelle, as she would later tell the psychologist, insisted it was just a relapse. >> i knew that i loved marty and i knew that i wanted to make it work in my heart.

>> but john diamond was devastated, or so said michelle. >> he said specifically, i'm going to kill myself, i can't live without you, you can't do this to me, i'm going to go drive my car off a bridge. >> it was awful, said michelle. diamond kept calling, made a scene at her office in front of some students she taught. he even threatened to call marty and tell him everything. so nearly a week after that romantic night in raleigh, michelle says she met john at a local restaurant to end the affair, gently but for good. >> we had the whole talk, can we be friends, and this can never happen again, never, never. he seemed very calm, very rational. >> so now it was december. time for peace and joy, christmas parties. one in particular at which the spirits flowed and the fuse burned down to its explosive

end. somebody was about to die. and somebody else wasn't taking any chances on missing. >> coming up -- >> it wasn't like bang, bang, bang, bang. it was bang, pause, bang, pause. >> which sounds more like what, an execution? >> you could take it that way, yes. >> when "dateline" continues. that's why i love light & fit greek non-fat yogurt. each delicious cup contains 12 grams of protein and 80 calories. it's nutrition that fits my healthy life. light & fit. do what fits you. it's nutrition that fits my healthy life. infused with eighty lavender flowers in every bottle. air wick essential oils smells so real we put it to the test with real people. this one smells more like lavender. that one. no way! i'll be darned. the complete air wick essential oils collection. before discovering nexium 24hr to treat her frequent heartburn, lucy could only imagine enjoying a slice of pizza.

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here in the heart of the american bible belt, on the fringe of vast sprawling army and air force bases, like a patient accommodating land lord, is fayetteville, north carolina. imagine, most of a suburban strip mall of strip clubs and a downtown which is charming, elegant even, and a scene about everything. it's an old town, fayetteville. that tower marks the spot where north carolina ratified the federal constitution back in 1789. i'm standing on what was a slave market. sherman fought battles here in the civil war. now it's a military town and 160,000 acres back there is the army's ft. bragg where soldiers prepare to go to war. nestled up beside that is the air force base. two institutions, two

professional military men, one woman. and that woman, michelle theer, now found herself caught between her husband, marty, the air force captain and her former lover, army staff sergeant john diamond who just wouldn't go away. >> i told him, i don't want to leave my husband. i never told him, i love you, i never said, i want to be with you. i mean, i think i was pretty straight up. >> now with the holiday season at full swing and a new commitment to her marriage, michelle and marty were on the road to raleigh, for a night out. traveling with them was another couple from her office. >> they had gone to this christmas party that she specifically asked her boss if marty could go. >> it was the date for office party standards and early morning since marty had to fly early in the morning. marty, michelle and the co-workers prepared to leave the

restaurant. then an interruption. michelle excused her. made a brief phone call out of earshot of the others. then the drive to fayetteville. one hour. they dropped the other couple at michelle's office then left for home. stopped on the way for gas. and then sitting at the gas pump, michelle told marty she'd forgotten something at the office. >> turning around and going back to the office to get some stuff that i needed so i could stay up and work that night. >> marty, parked behind the office building. michelle walked up an outside staircase, disappeared inside. marty, waiting in the car. apparently he got impatient, headed up the stairs to check out michelle. and that's when it happened. she found him, she said, at the bottom of the outside doorway. she could see the blood. she ran to the nearest store, called 911. >> somebody's shot?

somebody shot your husband? >> i think so. >> where are you at? okay. what's your name? >> michelle. >> within minutes fayetteville police and paramedics arrive and find michelle cradling her husband in a pool of blood, but it was too late. marty theer was dead. he was just 31. because marty was an air force captain, military investigators were soon on the scene as well as police. a joint investigation with the fayetteville pd. both teams were eager to speak to the only known witness, michelle theer. officers special investigations unit, vince -- >> she said what sounded like her three bangs of a car back firing. >> did she say what she did at that point? >> she opened the door and saw her husband laying at the bottom of the stairs. >> she told them she thought she

saw somebody moving in the bushes near the stairway but she wasn't sure. >> initially, i think police were looking at perhaps a robbery of some type. >> detectives combed the parking lot's surrounding area, but found no one on this cold, dark, december night. >> was a man who lived behind the office building who heard the shots fired, who later said that he said, "somebody's getting murdered out there because of the order in which the shots were fired. they were very calculated. >> it wasn't like bang, bang, bang, bang. it was bang, pause, bang, pause, a space between each of the five shots. >> which sounds more like what, an execution? >> you could take it that way, yes. >> at the top of that stairway were a few clues, bullets holes sprayed in the wall, sequins littered the landing.

looked like he was at the top of the stairs, shot from down below. >> i think that's what made him roll down the stairs, and the final shot was to the back of the ear. >> the kill shot? >> the kill shot. close range. >> they found shell casings in the parking loss. appeared to be from a isn't 9 millimeter handgun. but there were no fingerprints, no foot prints, no useful dna. but investigators did find marty's wallet on him, complete with cash and credit cards. >> marty theer was not robbed. the other thing was that it was a very, very cold night. not a night where a prowler would be out on the streets just looking to find someone. it made it very suspicious. >> investigators couldn't imagine who would want to kill such a wonderful man like captain marty theer. but, of course, out in this dark parking lot they didn't know any of what you know, not yet anyway. assuming what you've heard so far is the real story. and as you'll see, the question of what was true and what wasn't

could be very tricky indeed. >> michelle said she had gone back to her office because she'd forgotten something. so what took so long? coming up -- >> they found a candy wrapper that had been opened and in the trash can. it was almost like a scene where she had just gone upstairs and sat and waited for a few minutes. >> for what? when "dateline" continues. why are you checking your credit score? you don't want to live with mom and dad forever, do you?

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it was a week before christmas 2000 and ferretville was aglow, but not everywhere with the lights of christmas. and a few hours after air force captain marty theer turned up dead in the parking lot of his wife's office building, the news was out and it was big. michelle theer, now marty's grieving widow, told the police she was inside her office looking for a book when she heard someone firing outside. >> by all counts it was an assassination. >> greg buckner was a deputy district attorney at the time. >> someone would kill marty theer that night, no evidence of any robbery, no evidence of any other thing going on here. >> though inside michelle's office what they found seemed, well, a little odd maybe. >> she'd gone to the bathroom, the toilet had not been flushed.

they found a candy wrapper that had been opened and in the trash can. it was almost like a scene where she had just gone upstairs and sat and waited for a few minutes, because obviously to find a book wouldn't take very long. >> strange. hard to know what it meant, if anything. as down approached, michelle was allowed to go home, and later that morning her boss arrived. so the cops talked to him, too. >> during that interview it came out that she was having marital problems and was having some extramarital affairs. >> funny, michelle hadn't mentioned anything about that. so detectives went to her house to follow-up, and, sure enough, michelle did admit having an affair with staff sergeant john diamond. michelle also said she hadn't spoken to diamond in two days, but when pressed she remembered trying to call him unsuccessfully just before leaving that christmas party about 90 minutes before marty was murdered. so detectives decided to check

their cellphone records and discovered -- >> they have been calling each other regularly, minimum 20 times a day. >> now detectives paid a visit to john diamond, who freely admitted having a sexual relationship with michelle but claimed she was just one of many ladies in his life. and as for the night of the murder, he had an alibi. he was home with his family watching a movie. still, michelle must have harbored some sort of suspicion about john diamond, who was now a person of interest. not long after the murder, as she told detectives and that psychologist, she went to see diamond, conduct her own investigation. find out what he knew about marty's death. >> i said, do you know anything about this, do you know anybody who had anything to do with this, and he said, no, i would never do anything to hurt you, i know how much you loved him. i believed him. he looked so trustful. >> mind you, as police were soon aware, michelle had many

opportunities to question her friend, john, after her husband died. >> there were witnesses saying that he parked down a little side street and then walked through their yards, going in the back door of her house. >> he couldn't stay away from her. >> no, he was going there and staying all night. >> not commonly the way widows grieve, spending the night with the person of interest in her husband's murder. but michelle told psychologist dr. debbie leighton thole, she needed support from someone, anyone. >> she felt more alienated by family and friends and more threatened by the police. the only person in her life that was willing to be there for her was john diamond. >> i knew that i was depressed and i was getting more and more depressed and i think i went to john for comfort. >> a few weeks after marty's murder, michelle and john drove to florida for a long weekend.

michelle wanted to see a former professor for grief counseling, she said later, while diamond stayed with his sister, debbie. >> he acted as if nothing was wrong because he knows he didn't have anything to do with it, he didn't shoot him. >> so who did kill captain marty theer? was it possible john diamond actually executed hips romantic rival? he may have had a motive. police were very suspicious, but the physical evidence was, frankly, rather weak. so detectives kept digging in the arcane world of phone records. boring but sometimes revealing. and one telephone number in particular caught their attention, a call from diamond to one of his army buddies at ft. bragg. >> so we asked them if diamond had any access to any weapons. he said that he loaned diamond his personal pistol. >> which just happened to be a .9 millimeter beretta pistol,

the same kind of gun that killed marty theer. >> john diamond had actually borrowed the gun from him during the time period that the murder occurred. john diamond had possession of it. >> detectives were convinced diamond not only had access to a gun, but maybe even the actual murder weapon. did he still have it? well, apparently not. because just a short time after cops went to the home of diamond's army buddy asking about that gun, diamond made a phone call to ft. bragg and reported that his car had been broken into, and one of the things stolen from it was a .9 millimeter handgun. >> when we got there the passenger door had already been opened and there was a pile of glass sitting next to the rocker panel on the passenger's side. but if you look on the inside, there was very little glass. >> what did that tell you? >> he had the door open when he broke the window and then tried to make it look like it was

broken in. >> a bogus break-in? military police sure thought so. john diamond was arrested for admitting that he brought an unregistered gun on base. clearly diamond was now the prime suspect in the murder of captain marty theer, but was he really the killer? >> announcer: coming up, a secret about john and michelle's steamy affair becomes very public. >> she was taking him to these sex clubs and saying, "it's okay, go, you know, if you want to have sex with her, that's fine." and he just, wow, okay. >> when "dateline" continues. know what? no, what? i just switched to geico and got more. more? got a company i can trust. that's a heck of a lot more. over 75 years of great savings and service.

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aggressive geo blastoma and began treatment for the disease. national weather service downgraded hurricane lane to a tropical storm, but hawaii faces flash flooding and potential landslides throughout the weekend. more news at the top of the hour on msnbc live. ♪ welcome back to "dateline." i'm craig melvin. army staff sergeant john diamond was arrested for admitting he brought an unregistered gun on to a military base, the same type of wet on-used in the fatal shooting of his lover's husband. he was now the investigators prime sis expecuspect. but they needed more evidence. continuing with our story. >> a few weeks after the murder of theer, a fayette very police

detective named c.t. williams was asked to have a look at a couple of computers seized from michelle theer's home. >> i was looking for documents and text messages and e-mails. >> like an onion he peeled back the layers of texts which through they'd been deleted reappeared under his expert touch. boxed of deleted documents, 88,000 of them, buried deep inside michelle's hard drive. and out spilled some of michelle's most intimate sexual secrets. >> she seemed to be seeking affairs with a number of people over time. she was looking for an alternative lifestyle. she was seeking a partner escort for sexual clubs. >> that would be carolina friends, a swingers club. it boasted more than 10,000 members. and within michelle's lengthy list of e-mails detectives also discovered that not so innocent inquiry she typed seeking a rendezvous man. that was john diamond, of course, who replied and who the e-mail trail revealed quickly joined michelle in the

lifestyle. >> she was taking him to these sex clubs and saying, it's okay, go, you know, if you want to have sex with her, that's fine, go, i'm fine with it. and he just, wow, okay. >> but as investigators sorted through the sexually charged e-mail, they could plainly see a story as old as time. john diamond fell head over heels in love with michelle. >> he was her little puppy. to be controlled any way she wanted to control. >> he was like the child in the relationship. >> whatever she wanted, he was at her beck and call. >> hundreds upon hundreds of love-sick e-mails. john diamond appeared to be a map obsessed. i can't wait until you come back so we can take care of each other. you know, sex, sex, sex and of course, more sex. i know that we're meant to be together and are kindred soulmates. i will always love you, no matter how you've hurt me. >> you can tell it changed from a sexual relationship to a completely, totally enamored with her any way you can imagine.

>> he was gets desperate. >> he wants to be with her. he was willing to do anything. keep the woman he's totally in love with. >> anything? perhaps even kill the man who stood between him and michelle? >> she was beginning to set him up. she's playing to his emotions. she was pushing him away. push him away in some ways but without completely pushing him away. >> push/pull. >> she was manipulating him at that point. >> manipulating him into murdering her husband? why would she want to do that? >> there was a $500,000 life insurance policy taken out in 1999 on marty theer. >> the sole beneficiary? michelle theer. john diamond's family was outraged at such a theory. they were convinced michelle typed all those e-mails and sent them to herself to steer investigators away from her and to diamond. so he'd take the raft. >> he never once expressed a love feeling about her to me. unless you come to me with

handwritten letter that he was obsessed with her, i'll never believe that. >> how do you know that? >> because he told me. he did not want to marry her. he did not want to spend the rest of his life with her. >> according to debby, it was michelle who was obsessed with john. and never more so than when she gave debby two wedding rings to take to her brother who was by this time locked in. >> i think she was obsessed with him to the point she couldn't control him, she couldn't, you know, control the situation. >> she wanted to control it and if she gave him a wedding ring and he wore it, wouldn't that give her all kinds of reason to claim that he would do anything for her? including kill her husband? >> that could be. i don't know. what i got from him after he was arrested was he didn't want anything to do with her. nothing. >> with or without michelle, john was in big trouble. so he lawyered up with prominent fayetteville attorney, clay brewer.

>> i believe that he was an innocent man wrongly accused. that any rational interpretation of the circumstantial evidence is consistent with sergeant diamond not being the shooter. >> but military investigators were convinced diamond was the triggerman and decided to quickly proceed with their case against him. and michelle, to remain free. and what did she do? she left town. >> i think she planned to kill her husband a long time ago. i think she waited and researched and waited for that right person that would look and fit the part to pin it on. >> if that was true, michelle's plan was working perfectly because in a few short weeks john diamond would be on trial for murdering her husband. coming up, the prosecution's case against john and the defense's case against michelle. >> michelle theer was a brilliant, cunning, ruthless

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energy lives here. in the dead center of ft. bragg, north carolina, is a nondescript red brick building, this is where army staff sergeant john diamond found

himself, a prime suspect in the murder of air force captain marty theer. >> military justice is much swifter than civilian justice. so he goes to the article 32 hearing which is like the grand jury. they immediately find cause and they charge him. >> and nine months after the murder, in a small ft. bragg courtroom, diamond went on trial before a military jury. >> diamond was very, very cocky at the beginning. he would laugh and joke with reporters in there. he was just so sure that he was going to be acquitted. >> john diamond wasn't the star of his own trial. michelle was. she was free as a bird then. though still under investigation by fayetteville civilian homicide cops. and here she was called to testify at her former lover's military trial. >> she shows up, her hair is now, like, a red color that she's colored it. she's lost a bunch of weight. and she's got a gaggle of media following her into the building. >> it was all image. no substance.

michelle took the stand but took the fifth. the prosecution's case against diamond, its accusation was simple. driven by his obsession for michelle, he conspired with her to kill her husband by borrowing the gun, arranging to be in a position in that dark parking lot, waiting until marty theer had placed himself in the kill zone at the top of the staircase outside michelle's office. and fired the five shots that killed him. as for diamond's alibi that he was home with his wife watching a movie, that now ex-wife came to court and told the jury that the evening wasn't quite like that. half way through the movie his phone rang, she said and suddenly he was gone. what's more? >> her mother heard him come home, you know, in the wee hours and wash clothes. >> true? maybe not said defense attorney brewer. her story changed after she talked to police. >> she was afraid of the

government. i don't think that she was telling the truth. >> had she been pressured? besides, said the defense, there was no dna. no footprints. no fingerprints to prove diamond shot marty theer. diamond was a trained shot shooter but the ones that hit marty were mostly badly aimed, must have been a work of an amateur, said the attorney. someone like michelle. >> michelle asked for the gun several days before the murder, told him her husband was abusive and she was afraid of him. he gets the gun and gives her the gun. he didn't think she was going to use him for the gun. >> did she use him? somebody she could use to serve his purposes? >> she set this up to kill her husband because she wanted the insurance money and for sergeant diamond to take the fall. michelle theer was a brilliant,

cunning, ruthless woman who wanted her husband dead. >> the military jury, however, didn't see it quite that way. >> the verdict was swift. guilty as charged. and from that moment on, his demeanor changed. i mean, it was, like, somebody just sucked the air out of him. the john diamond full of bravado and ego just shrivelled away. >> diamond was sentenced to life in prison without parole. at the time his family was furious, convinced he was framed. >> you don't expect to be convicted on theory and myth and what ifs. show me blood, show me a gun. show me the timeline that works. show me those facts. i'll believe until the day i die that she killed her husband, that she planned to have my brother go down for it so she could live this happy, wonderful life. >> curious thing that.

john diamond settled into a life in prison, people around fayetteville could see to their great disapproval that michelle went on with a life uninterrupted. then quite suddenly they didn't see her at all because michelle theer disappeared. >> coming up -- michelle wasn't just a missing woman. she was also now a wanted woman. >> there's some speculation that she was tipped off that she had been indicted because she seemed to really sort of fall off t michelle wasn't just a missing face of the woman. earth. >> she was also now a wanted woman. when "dateline" >> there's some speculation that continues.

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welcome back to "dateline." shortly after john diamond was convicted in the murder of her husband, michelle fear did something unexpected. she left fayetteville, north carolina, without a trace. authorities weren't done with her yet, but would they be able to track her down? hear what the conclusion of deadly ambush. >> federal prison, doing time doesn't come much harder than it does here. this is where john diamond was serving a life sentence for murdering air force captain marty fear. but his former lover, michelle seemed to have dropped right out of sight. where was she? people weren't seeing her around

fayetteville. the d.a. meanwhile was convinced she must have conspired with john diamond to kill her husband. she was the brain, he was the brawn or in this case, the shooter though it was all circumstantial it was persuasive. >> i don't think there was any question as to who was involved, diamond and her together mpl. >> the evidence, a life insurance, the affair, the access to a murder weapon, those e-mails, the coverup, taken together it was enough to convince a grand jury and finally in may of 2002, nearly 18 months since her husband was killed, michelle theer was indicted for first degree murder and conspiracy, but arrested? no. why? >> there's some speculation that she was tipped off that she had been indicted, because she seemed to really sort of fall off the face of the earth right before that came down.

>> michelle theer vanished. no one, not even her family knew where she was. lauderdale by the sea is a charming little town just north of miami, quaint and quiet, low profile. in the summer of 2001, cindy, a local landlord met with a woman who wanted to rent a room at her cottage. >> he gave her name as liza pendragon. she told me she was on the run from an abusive boyfriend from california. she made friends around the neighborhood. before long she had a new beau. she kept in touch with her family very carefully, secretly. she only called on pay phones for example and that rarely. >> two months after michelle arrived in florida she asked her boyfriend to call her parents, pass on a message, use a pay phone, she told him.

and maybe he forgot or perhaps he didn't tell them why, but he called from his parents' house phone. u.s. marshals were monitoring. they looked up the number that had called michelle's parents. >> the database told them that this woman had a son in his mid 20s who lived in the south florida. >> did he know the missing michelle? the cops found him, staked him out. then followed him to that little white beach cottage where he and michelle were in for a big surprise. >> following a developing story out of florida. a woman wanted for the murder of her husband, has been arrested in florida. >> at the time of her arrest inside the apartment we found magazines describing ways to go under cover in the united states, obtain new identity. >> books too on learning spanish, travel guides for several latin countries, an

array of fake ids and then there was michelle's appearance. >> she had changed her appearance. cud and dyed her hair. had some plastic surgery done. >> do you have anything at all to say? >> few days later, her face still red and swollen and smeared with ointment from cosmetic surgery was driven back to fayetteville. she was charged with first degree murder and locked up without bail. and two years later in september 2004 after turning down a plea deal that would have imprisoned her for ten years, the prosecutor laid out his case against michelle theer. the proof, for one thing, all those intimate e-mails would show how michelle manipulated diamond into a fatal frenzy and made him her fall guy. >> she got john diamond to the point that he was so upset if he couldn't have her, he was going to kill himself. if you're willing to kill yourself, it would not take much

for you to redirect that and kill someone else. it got to the point where he was willing to kill marty. >> that point arrived said the prosecutor after that office christmas party when michelle called diamond to tell him that she and marty were heading to the kill zone, the parking lot of her office building but she needed him there alone. so after they dropped two coworkers at the lot said the prosecutor, michelle made a crucial move that linked her to the murder. remember they began driving home, stopped for gas, but then michelle by her on admission had marty return to the office supposedly to pick up some work she needed. and while she was in the office, marty became impatient, went up those stairs to check on her. and thus walked in to an ambush. >> when they left, there would have been no way for that shooter to have any reason to believe that they were coming back lest he had known to prior conversation he was going to bring him back to that location, go up into her business, leaving

him outside the door so that he could then murder her husband. >> that was really your smoking gun. >> that was the smoking gun that tied her to it. >> michelle did not testify nor did john diamond. her attorney belittled the the state's evidence as thin and circumstantial. among those speaking for michelle, psychologist hired by the defense to interview michelle about her relationships to testify as an expert witness. those were the recorded conversations, excerpts of which you heard earlier. the doctor told the jury michelle wasn't manipulating diamond by stopping and starting their illicit romance, no, it was something else. >> when somebody's in a long-term affair there does tend to be a pattern of pulling away and then coming back together. an inability to be decisive. that's not unusual with affairs. >> besides, claimed the defense, being involved with another man

didn't mean michelle was also involved in murder. the two sides battled through three months of trial time from labor day past thanksgiving. 11-week trial. three hour deliberation. the verdict, guilty. >> she stood up, you know, they put the handcuffs on her and she walk out the courtroom and she never looked back into the courtroom area, not even to her family. >> she now sits in a north carolina prison halfway across the country from her coconspirator, john diamond. today these former lovers share only one thing, life without parole. >> his supporters are heart felt in their certainty that she was the bad one. she did it all. he didn't do anything. >> and her supporters all blame him and say he did it without her knowledge because he was in love with her and she was breaking up with him. >> michelle theer rolled the diagnosis. she turned down a deal which would have released her before

long. instead, the woman who followered hr dissatisfaction to an internet romance went on trial and as a result will die in prison. >> that's all for this edition of "dateline." i'm craig melvin. thank you for watching. hey, there. good morning, everyone. i'm a i'm alex here in new york. it is 7:00 a.m. in the east. 4:00 a.m. west and here's what's happening right now. immunity. long-term trump organization cfo cuts a deal with federal prosecutors. >> you don't eat a big fish to eat a smaller fish. he gets immunity in the hopes he can help with someone else and cohen doesn't look like the big fish they would be going after he