they gave tara peace and justice. >> that's all for this edition of "dateline." i'm craig melvin. >> 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 many. then, suddenly, there was one man less. >> it wasn't like, bang, bang, bang, bang. it was bang, pause, bang, pause. >> which sounds like what? execution? >> you can put it that way, yes. >> a cold-blooded killing.

did someone drive her to murder? or did she? >> she was a 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 crossfire of a lover's triangle. here's 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. >> where are you at?

>> reporter: michelle was, no doubt about it, dissatisfied. here she was, young, successful, attractive. and it wasn't exactly boredom that was eating at michelle. she was starting a new career as a psychologist, often counseling troubled couples. >> i think she was newly licensed. that was her first job. >> reporter: she would laugh that events would propel her that newspaper reporters would be poking around in her past. >> michelle, to everyone i spoke to, was trying to be somebody. she was trying to become a professional. >> reporter: michelle at an early age, always seemed confident in getting what she wanted. she was 16 when she started

dating marty. marty was a couple years older, worldly, bright, had big plans. he wanted to be a astronaut. he went to the air force academy. she was 20, when she married him, in the famous chapel outside of colorado springs. >> you may kiss your bride. >> reporter: this was 1991, where marty was everything she ever wanted. long before she talked to that psychologist. agreed to talk about the events that were about to come and the 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. >> reporter: he was the dashing officer back then. she, his lovely bride. the future she imagined, an e

endless honeymoon, where marty's career would take them to exotic destinations around the world. she didn't imagine that world would be posts in oklahoma, and fayetteville, north carolina. marty was a captain by then. flew one of those huge c-130 cargo planes. all that time alone, not that easy on a marriage, that she revealed with tape recorded interviews with psychologist debbie cole. >> marty was away for extended periods of time. she was having a hard time with that. she was getting lonely. >> reporter: sometimes he was gone for months, sometimes when he did come home, military

families have gotten to know that adjustment period too well. they bickered about having children. he wanted them, she didn't. she was worried she would be stuck raising them herself, where she was lonely. >> loserville. no one to hang out with. no one to pick up the phone and call. >> reporter: that was about the time it started. harmless, raleally, a few key strokes. sexy brunette seeks rendezvous man. and not long after, she got a response. from him. his name was john. john diamond. >> john was a lady's man. >> reporter: debbie could see her brother responding to a

solicitation like michelle's. >> my brother has a great personality. haez he's an attractive guy. >> reporter: after meeting online, they met in person, at a restaurant. >> talked about movies, music and things that marty and i didn't talk about. >> reporter: john diamond was an army staff sergeant, trained at ft. bragg and was highly regarded, decorated. >> he was a good soldier. he was a playboy himself. he left the first wife and they had a son together. >> reporter: michelle didn't know that john was still married. maybe it didn't matter. at least not then. she loved the sex, the attention, the excitement. >> he was very attentive. he was very affectionate. he was very adoring.

yeah. it felt great. >> reporter: what made her so desirible to him? >> it was the sex. >> reporter: for michelle, it was more lust than love. >> she felt the affair did not take away from the fact she loved marty. she said he was the love of her life. >> reporter: and marty? he was in the dark, of course. when michelle told him their marriage was in crisis, and he wouldn't agree to see a counselor. >> he wouldn't see a counselor and i moved out. he was shocked. >> reporter: she moved in with john diamond. >> he would rub my feet, if i wanted him to. >> reporter: he never met a person like her before. >> she challenged him in ways he

had never been challenged before. she was strong and exciting for him. >> reporter: was he enough for her? apparently not because after three months on her own, michelle went back to marty. >> she felt like the marriage could survive. despite everything that happened that she could make it. >> reporter: john and michelle's six-month affair seemed to be off. then, apparently, it was back on. the two traveled to the tropical island of saba, where michelle interviewed for a job at a university. and later that fall, a romantic rendezvous at a hotel where they would celebrate her 30th birthday. but michelle told the psychologist it was just a relapse. >> i knew i loved marty. i wanted to make it work in my

heart. >> reporter: john diamond was devastated. >> he said, i can't live without you. you can't do this to me. i'm going to drive my car off of a bridge. >> reporter: it was awful, michelle said. diamond kept calling. made a scene in front of her office, and threatened to call marty and tell him everything. a week after the romantic night in raleigh, she met john at a restaurant to end the affair, gently but for good. >> it would never happen again. never, never, never. he seemed calm and very rationale. >> reporter: now, it was december, time for peace and joy, christmas parties. one in particular, at which the spirits slowed and the feud 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? execution? >> you could take it that way, yes. >> when "dateline" continues. ♪ ♪ ♪ ♪ walgreens... battle beautifully seresto, serjake...eresto. seresto, seresto, seresto. whatever your dog brings home to you,

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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 landlord, 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 pope

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. >> reporter: it was sedate by office party standards and ea y

early, 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 herself. 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. [ gunshots ] she found him, she said, at the bottom of that 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. >> reporter: 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, making this a joint investigation with the fayetteville p.d. both teams were eager to speak to the only known witness, michelle theer. officers special investigations unit, vince castillo. >> she said what sounded like her three bangs of a car back firing. >> reporter: did she say what she did at that point? >> she opened the door and saw her husband laying at the bottom of the stairs.

>> reporter: she thought she saw someone moving in the bushes, near the stairway. but she wasn't sure. >> initially police were looking at perhaps a robbery of some type. >> reporter: detectives combed the parking lot's surrounding area but found no one on this cold, dark december night. >> there 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. it was bang, pause, bang, pause. a space between each of the five shots. >> reporter: which sounds like what? an execution? >> you could take it that way, yes. >> reporter: at the top of the stairway were a few clues. bullet holes sprayed in the wall.

sequins from his outfit littered the landing. 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 left ear. >> reporter: the kill shot. >> the kill shot. close range. >> reporter: they found shell casings in the parking lot. appeared to be from a 9 millimeter handgun. but there were no fingerprints. no footprints. no useful dna. investigators did find marty's wallet. still on him. complete with cash and credit cards. >> marty theer was not robbed. the other thing that 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. >> reporter: investigators couldn't imagine who would want to kill such a wonderful man like captain marty theer. but of course, out on 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'd 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 in the trash can. it was almost like a scene where she had gone upstairs and sat and waited for a few minutes. >> for what? when "dateline" continues. to b. it's not sexy. or delicious. or fun. but since you need both car and home insurance, why not bundle them with esurance and save up to 10%? which you can spend on things you really want to buy, like... well, i don't know what you'd wanna buy because i'm just a guy on your tv. esurance. it's surprisingly painless.

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christmas 2000, and fayetteville 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 accounts it was an assassination. >> reporter: greg buckner was a deputy district attorney at the time. >> someone would kill marty theer, that night, no evidence of robbery, no evidence of any other thing going on here. >> reporter: 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 opened and in the trash can. it was almost like a scene where she'd gone upstairs and sat and waited for a few minutes because obviously to find a book wouldn't take very long.

>> reporter: strange. hard to know what it meant, if anything. as dawn 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 she was having marital problems and was having some extramarital affairs. >> reporter: 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. detectives decided to check their cell phone records and discovered -- >> they've been calling each other regularly, minimum 20 times a day.

>> reporter: 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. >> if you know anything about this, you know anybody who had anything to do with this, please tell me. i would never do anything to hurt you. i know how much you love --

>> reporter: mind you, as police were soon aware, michelle had many opportunities to question her friend, john, after her husband died. >> witnesses said he parked down a little side street then walked through their yards going through the back door of her house. >> reporter: he couldn't stay away? >> going through, staying all night. >> reporter: not commonly the way widows grieve, spending the night with the person of interest in her husband's murder. michelle told psychologist dr. debbie leighton she needed support from someone, anyone. >> she felt more alienated from 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. i was getting more and more depressed. i went to john for comfort. >> reporter: 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. he knows he didn't have anything to do with it. he didn't shoot him. >> reporter: who did kill captain marty theer? is it possible john diamond executed his 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. >> reporter: which just happened to be a 9 millimeter berretta pistol, the same kind of gun that killed marty theer. >> john diamond had actually borrowed the gun from him during the timeframe when the murder occurred, john diamond had possession of it.

>> reporter: detectives were now 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, which he claimed to have left in the base parking lot, 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. if you look on the inside, there was very little glass. >> reporter: 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. >> reporter: a bogus break-in? military police sure thought so. john diamond was arrested for

admitting 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? 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. with this one little nexgard chew comes power, confidence, reassurance you're doing what's right to protect your dog from fleas and ticks for a full month. this one little nexgard chew is the #1 vet recommended protection. and it's the only chew fda approved to prevent infections that cause lyme disease. plus, it's safe for puppies. there's a lot of power in this one little nexgard chew. nexgard. what one little chew can do.

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i'm dara brown, with the hour's top stories. william barr says he may release a summary of robert mueller's robert by the end of the weekend. democratic leaders say a summary isn't enough, with some calling for the full report to be released to the public. and flooding along the missouri river is causing flooding in the midwest. high waters led to a sewage

spill from a waste water treatment plant, contaminating the water there. now, back to "dateline." welcome wback 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 kind of weapon that was used in the shooting of his lover's husband. he was now the prime suspect but they needed more evidence. continuing with our story, here's keith morrison. >> reporter: a few weeks after the murder of captain marty theer, well, police chased more earthbound clues. a fayetteville police detective named c.t. williams was asked to have a look at a couple of computers seized from michelle theer's home. see if they might contain any clues. >> i was looking for documents

or text messages or e-mails. >> reporter: like an onion he peeled book the layers of texts which though they'd been deleted reappeared under his expert touch. boxes 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. >> reporter: 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.

>> reporter: 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. >> reporter: he was like the child in the relationship. >> whatever she wanted, he was at her beckoning call. >> reporter: hundreds upon hundreds of lurid 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. >> reporter: he was getting desperate. >> he wants to be with her. he was willing to do anything. keep the woman he's totally in

love with. >> reporter: 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. >> reporter: she was pushing him away. >> push him away in some ways but without completely pushing him away. >> reporter: push/pull. >> she was manipulating him at that point. >> reporter: 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. >> reporter: 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 rap. >> he never once expressed a love feeling for her, to me. unless you come to me with handwritten letter that he was obsessed with her, i'll never believe that.

>> reporter: 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. >> reporter: 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 the brig. >> i think she was obsessed with him to the point she couldn't control him, she couldn't, you know, control the situation. >> reporter: 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. >> reporter: 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. >> reporter: but military investigators were convinced diamond was the triggerman and decided to quickly proceed with their case against him. and michelle, remained 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. >> reporter: 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 woman who wanted her husband dead. >> when "dateline" continues. ♪

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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. >> reporter: 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. >> reporter: 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. halfway 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. >> reporter: 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.

>> reporter: 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 sharpshooter but the ones that hit marty were mostly badly aimed, must have been a work of an amateur, said the attorney. an amateur like michelle. >> michelle asked for the gun several days before the murder, told him her husband was a beast and 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. >> reporter: did she use him? know that he was 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.

>> reporter: 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. >> reporter: diamond was sentenced to life in prison without parole. 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. >> reporter: 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 the face of the earth. >> when "dateline" continues.el" c which most pills don't. c flonase helps block 6 key inflammatory substances. most pills only block one. flonase. have a skincare routine. but what about a lip care routine? pay your lips some attention. the chapstick total hydration collection. exfoliate nourish naturally enhance your lips. chapstick. put your lips first.

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welcome back to "dateline." michelle feared something unexpected. she left fayettville, north carolina, without a trace. authorities weren't done with her yet, but would they be able to track her down? here with the conclusion of deadly ambush is keith morrison. >> leavenworth 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 fayettville. the d.a., meanwhile, was convinced she must have conspired with john diamond to kill her husband. she was the brains.

he was the braun, or in this case the shooter. though it was all circumstantial. it was persuasive. >> yorjs every i don't think there was any question as to who was involved, doimd and her together. >> the evidence? life insurance. the affair. the access to a murder weapon. those emails. the coverup. taken together, it was enough to convince a grand jury. finally, in may of 2002, nearly 18 months since her husband was killed, michelle fear 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, want 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 geazy, a local landlord, met with a william who wanted to rent her room. >> i let her sign a six-month lease. she seemed well spoken, intelligent. she told me she was on the run from an abusive boyfriend in california. >> she made friends around the neighborhood. before long she had a new beau. liza, it was really michelle, of course, 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 to pass on a message, use a payphone, she told him. maybe he forgot or perhaps he didn't tell them why, but he called from his parents' house phone. u.s. marshalls were monitoring.

they looked up the number that had called michelle's parents. >> in the database, it told them that this woman had a son in his mid 20s who lived in 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 ray of fake id's, and then there was michelle's appearance. >> she had changed her appearance. cut and dyed her hair. had some plastic surgery done.

>> do you have anything at all to say? >> a few days later michelle, her face still red and swollen and smeared with ointment from cosmetic surgery, was driven back to fayettville. 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 emails would show, said the prosecutor, how michelle manipulated diamond into a fatal frenzy and made him her fall guy. >> she got to the point where he was so upset that he couldn't have her, he was willing to kill himself. if you are willing to kill yourself, wouldn't take much for you to redirect that and kill someone else. michelle directed him. 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 co-workers at the lots, said the prosecutor, michelle made a crucial move that linked her to the murder. remember, the theers began driving home and stopped for gas. then michelle by her own admission had marty return to the office. supposedly to pick up some work she needed. while she drawedled in the office, marty became impatient, went up those stairs to check on her. that's when he walked into an ambush. >> when they lay off, there would have been no way for that shooter to have in reason to believe they were going to come back unless he had a prior conversation. michelle left him outside the door so that he could then murder her husband. >> that was really your smoking gun. >> smafs the smoking gun that

tied her to it. >> michelle did not testify. nor did john diamond. her attorney belittled the state's evidence as thin and circumstantial. among those speaking for michelle, psychologist dr. debbie lleyton thole. she was hired by the defense to interview michelle about her relationships and 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 manipulatiing diamond by stopping and starting their romance. no, it was something else. into when somebody is in a long-term affair, there something tend to be a pattern of pulling away and then coming back together. an inability to be decisive. that's want 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 true 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 walked out the courtroom, and she never looked back into the courtroom area. not even towards her family. >> michelle theer now sits in a north carolina prison halfway across the country from her co-conspirator 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. >> 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 dice. she turned down a deal which would have released her before long. instead, the woman who followed her 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 krig melvin. thank you for watching. good morning, everyone. i'm alex widtt. 6:00 a.m. here in the east. 3:00 a.m. out west. here's what's happening. waiting game. both parties and the president on technology anticipating first word from ag barr on the mueller report. that is expected today. >> donald trump, his family members, or any of his associates commit any crime. >> focus on the family. the next step for congress once the mueller news drops. who might be first in line? twitter silence. not a single word from president trump since the big mueller news. what's behind that strategy?