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Fatal attraction

After making a really bad choice, a husband who thought he could play around learned too late that he was playing with fire.

Scenes from a life, from a marriage: Love. Family. Betrayal. Jealousy. Obssession. Death.

A fatal attraction.

Ignacio Garraus met Heather Hodges met in college. It was love at first sight.

Josh Mankiewicz, Dateline NBC: How long before you knew this was the woman?Ignacio Garraus: Oh, right away.

In 1991, they married. He became a cop in Greeley, Colo. It was hard work, sometimes dangerous, but Ignacio was good it at, eager to help people. At the same time, Heather took on a difficult job of her own: being a cop's wife.

Ignacio Garraus: She worried most about when I was undercover, when I was a narcotics officer. And I'd never tell her when I'd to drug deals and stuff like that. Because it would only freak her out.

Shielding Heather from the ugly side of Ignacio's life: it was a natural reflex for Ig, as it is for a lot of people who carry a badge. But it would turn out to be the beginnings of a kind of "don't ask, don't tell" side to their marriage.

Josh Mankewiecz: They were happy?Wendy Jones: Yeah they were very happy. They were very happy.

Wendy Jones is Heather Garraus' sister. Jayme Harris is Heather's best friend.

Josh Mankiewicz: Between the two of you, you knew all Heather's secrets?Jayme Harris: I think we finished each other's sentences on the phone.

On the phone to one another perhaps two times a day, these two know Heather better than anyone, maybe even better than the man she married. And the woman they describe is not unlike a saint.

Jayme Harris: Friendly to everybody, everybody's friend.

Six years after they married, Ig and Heather welcomed a daughter, Victoria. They seemed like a picture-perfect family.

But the problem with marriages made in heaven is that they have to be lived here on earth. In early 2003, Heather's mother died of cancer. Her illness came not long after Heather's father had also passed away from a heart attack, and Heather started to buckle under the combined weight of all that sorrow.

Josh Mankiewicz: Did she seem to sort of change physically and mentally during that time a little bit?Jayme Harris: We knew she was sad. I don't think everybody knew.

But her husband knew. And although Ignacio tried hard to be understanding, it was hard for him as well.

Ignacio Garraus: Heather kind of started developing pretty hefty anxiety attacks and depression. And they had her on some medications that really put the brakes on her.

It was as if a different person had come to live inside Heather Garraus' body. Heather, normally so concerned with others, suddenly couldn't seem to get out of her own head. And, Ignacio says, thanks to the side-effects of the anti-depressant drugs she'd been prescribed, a seamless marriage started to fray at the edges.

Ignacio Garraus: And she'd come home during that year. And eat. And then go up to the room and we wouldn't see her till the next day. And that went on for a year. And intimacy became absent in our relationship. Josh Mankiewicz: So you felt what? Estranged? Disaffected? Unloved?Ignacio Garraus: Unloved. Neglected. And angry.

There's an easy way out of that, of course. It's one you can probably see coming. Your sex life is only a memory? You find someone else. Someone more exciting.

It's one of the times when life and art imitate each other, like when Michael Douglass meets Glenn Close in the movie "Fatal Attraction." Michael Douglas, who's married, has a fling with Glenn Close, who plays the other woman.

In real life, Ignacio and Heather had already discussed the consequences of exactly this scenario.

Josh Mankiewicz: Heather always told you that if you ever cheated on her--Ignacio Garraus: She'd divorce me.Josh Mankiewicz: She made that very clear?Ignacio Garraus: Very clear. She was stone cold clear about that.Josh Mankiewicz: Is that what kept you on the straight and narrow? Or were you married to the right woman?Ignacio Garraus: I was married to the right woman.

And as you'll see, he probably was. But the right woman wasn't paying Ignacio Garraus enough attention. Which left an opening for the wrong woman.

Josh Mankiewicz: And then along came Shawna?

Ignacio Garraus: Yes.

It was the summer of 2004. Officer Ignacio Garraus was keeping the streets of Greeley, Colo., safe, while at the same time placing his marriage in danger.

He'd been married for 12 years to his longtime love, Heather. But Heather had become distant, and now Ignacio had met someone else.

Like a lot of affairs, it was someone he met at work. Shawna Nelson was a dispatcher, frequently the voice on the other end of the police radio when Ignacio was out on a call.

Ignacio Garraus: She went out of her way to help me. I just figured, you know, she was a good gal.Josh Mankiewicz, Dateline NBC: When did it become clear to you that maybe there was something else there?Ignacio Garraus: We started running into each other at Starbucks at Westlake. And we started talking about, you know, some issues. And she was having some problems with her husband. And I obviously was having some problems with Heather. And she -- you know, we started confiding in each other. And one night it became intimate.

It was the proverbial first step down a slippery slope.

Josh Mankiewicz: You knew it was wrong when you did it?Ignacio Garraus: Absolutely.Josh Mankiewicz: And you knew that Heather had said to you, many times, "If you ever cheat on me, I'm out of here."Ignacio Garraus: Yes.Josh Mankiewicz: And you did it anyway? I guess my question is--Ignacio Garraus: Why did I?Josh Mankiewicz: Why more than once?Ignacio Garraus: Because the problem still existed. And then once you've soiled yourself, dirtied yourself, once you're in the mud, what's the difference with having a little bit more mud on you, you know?

Shawna Nelson was a mother of two, married to a local deputy sheriff . And not only did she and her husband Ken work in law enforcement, she was now involved with a police officer in the same town.

For now, Shawna was able to keep those different parts of her life from touching one another.

For Ignacio, their affair was easy to maintain because he frequently worked nights, while his wife Heather worked days at a local credit union. And because, simply put, Heather trusted him. At the time, she shouldn't have.

Josh Mankiewicz: How many times would you see your girlfriend? Be intimate with your girlfriend? Have sex with her? And then go home and there's your wife saying, "Hi, honey."Ignacio Garraus: Oh, probably once a week at least. The sex.Josh Mankiewicz: And how'd that make you feel?Ignacio Garraus: Oh, terrible. But I still did it.

Ignacio Garraus isn't running away from the choices he made. As you'll see later, he couldn't if he wanted to. But at this point in the affair with Shawna Nelson, he felt he had the upper hand.

Josh Mankiewicz: Was Shawna Nelson the first woman you ever stepped out on your wife with?Ignacio Garraus: Yes.Josh Mankiewicz: Why her?Ignacio Garraus: I think because of her aggressive nature. I think I felt that all she wanted to do was sleep with me and be done with me.Josh Mankiewicz: So she was safe?Ignacio Garraus: She was safe.

For all his cop's instincts, Ignacio couldn't have been more wrong.

Jennifer Morrison: I saw what happened to people that crossed Shawna. And I didn't want to be one of those.

Jennifer Morrison was Shawna Nelson's supervisor at county dispatch, and says the Shawna she worked with was anything but safe.

Jennifer Morrison: She tended to have a lot of affairs. And when she was involved with someone, she would become very protective of that person and view that person's spouse as a threat to herself. So she would make statements about wanting to get rid of the other person.Josh Mankiewicz: We're not just talking about Heather Garraus here? This was standard operating procedure for Shawna whenever she was involved with someone?Jennifer Morrison: Yes. The hostility never seemed to be directed at the person that was refusing to break up a relationship with their spouse or girlfriend. It seemed to be more directed at the woman in the relationship.

And that's exactly how it started with Heather. They didn't know one another, but suddenly Shawna was showing up at places like the supermarket, clearly seeking Heather out.

Josh Mankiewicz: How many times did Shawna approach Heather in public?Wendy Jones: I know of at least—four?

Four times at least when Shawna Nelson would find Heather Garraus somewhere in Greeley and begin verbally abusing her in public. Heather's sister Wendy says it often happened when Shawna was with her friend Michelle Moore.

Wendy Jones: Shawna would be with Michelle.Jayme Harris: And she was meaner when she was with Michelle.Wendy Jones: They would both point at Heather and laugh and call her names.Josh Mankiewicz: What kind of names?Jayme Harris: Like, under their breath, like "bitch."Wendy Jones: "Bitch" was the big one. Josh Mankiewicz: Heather must have told you once or twice that she'd run into Shawna and Shawna had been explicitly, deliberately nasty to her? Did you talk to Shawna about that?Ignacio Garraus: Well, yes. I go, "Well, what the hell are you doing?" You know, "What is Heather doing to you? Nothing. Leave her alone. She's the innocent. Just stay out of it." Oh, and then she got very angry and she'd go, "Oh, I'm sorry. I'm not allowed to talk about Snow White."

And Heather, who wanted everyone else to like her, found that huge dose of attitude from Shawna Nelson impossible to understand.

Jayme Harris: She used to say, "Why is this happening to me? I'm a good person."Wendy Jones: Yes.Josh Mankiewicz: And she never put it together in her head that maybe her husband was having an affair with this crazy person?Jayme Harris: I don't know. I think a little bit.Wendy Jones: I think she did. I think she put a lot of it together. I do.Josh Mankiewicz: But she didn't want to believe it?Wendy Jones: No.

To Heather, Ignacio explained it away by saying Shawna just had a crush on him. The truth was that Shawna was making clear to Ignacio that for her, this was now much more than a fling.

Ignacio Garraus: I mean, like three months in and she's like telling me that I'm the one. I'm the love of her life. Don't I love her? I'm like, "Whoa. Listen. I'm not leaving my life. I love my wife. This isn't going to happen." Josh Mankiewicz: In retrospect, that might have been a good time to tell her you didn't want to see her anymore?Ignacio Garraus: Oh, absolutely. Of course. I could look back and I wish I could change a lot of different things. But I didn't know that her interest in me would become an obsession.Josh Mankiewicz: You ever seen the movie "Fatal Attraction"?Ignacio Garraus: You got it. Yes.

He says that just like the Glenn Close character in "Fatal Attraction," Shawna wouldn't be ignored either. She knew that Heather had promised to leave Ignacio if he ever cheated on her, and now Shawna was threatening to play that card.

Ignacio Garraus: It always was that thing ebbing in the background, underlying theme during the whole relationship was--Josh Mankiewicz: If you--Ignacio Garraus: --"Be a good boy, Ig. Be a good boy, Ig and I won't tell Heather. You do what I say."Josh Mankiewicz: That must be emasculating?Ignacio Garraus: Oh, absolutely. Having tables turned on you.Josh Mankiewicz: I'm a cop. I'm a man. You know, I should be more in control of this. I should be. And then somehow the person I decide to step out on my marriage on turns out to be a sociopath.

If you thought the parallels to "Fatal Attraction" were over, think again.

It's the fall of 2004, and Greeley, Colo., police officer Ignacio Garraus is feeling trapped in an extramarital affair. He'd like to get out, he says, before his wife Heather catches him. But his mistress, Shawna Nelson, won't hear of it. She's keeping him in her bed by threatening to tell his wife.

Ignacio Garraus: It was a daily thing where it's like, "How do I get out of this? Told Shawna that I wasn't going to leave Heather -- you'll do your thing. I go do my thing."Josh Mankiewicz, Dateline NBC: You tried that argument before?Ignacio Garraus: It didn't work. No. She wanted me. Josh Mankiewicz: Did you ever think about calling her bluff and saying, "I'm going to tell my wife and we're going to let the chips fall"?Ignacio Garraus: I thought about it … I didn't want to lose Heather, so I didn't want to risk it.

And he never asked for help from friends or family.

Ignacio Garraus: I walked a very lonely path on this.Josh Mankiewicz: Yes. Because of your pride.Ignacio Garraus: Oh, absolutely. Oh, you want me to not concede to that? My pride's probably what got me into this to begin with.

Greeley is a small town, and for Ignacio it was getting smaller all the time because there was no getting away from Shawna. She worked police dispatch so she always knew where to find him during his shift, and after hours it would be easy for Shawna to drive by Ignacio's house and see if his car was in the driveway.

He says he wanted to break up with Shawna, but discovered that whatever he tried, Shawna could find a way around it.

Ignacio Garraus: Basically, I pushed her away and changed the phone number and everything like that. But then, with the police department ties that shared pagers and things, text messaging, she had access still to that stuff.

There were text messages. Phone calls. Shawna was in Ignacio's life to stay.

Ignacio Garraus: And then finally she said she was pregnant. And I was like, you know, "I thought you were on the pill?" She says, "I am on the pill." I go, "Then you got pregnant on the pill?" And we went back and forth. And it was agreed between us that she would have the abortion. And I went with her. And I paid for it.

A pregnancy. An abortion. For Ignacio, it was getting worse and worse.

Josh Mankiewicz: During this time, your wife is thinking what? Is she noticing anything? Asking you if something's wrong?Ignacio Garraus: Yes. She's always asking me why I seemed so stressed. So wound up.Josh Mankiewicz: And you'd say what?Ignacio Garraus: Just work.

Heather's sister Wendy and her best friend Jayme say Heather did have her suspicions, but never allowed herself to think what might really be happening, what her husband might really be up to.

Wendy Jones: She knew something was up but she didn't want to believe it.

It was getting more and more complicated. Ignacio wasn't being faithful to Heather, or to Shawna either. He had, he says, a few one-night stands with other women. Heather never knew. But Shawna, his mistress, suspected and started keeping Ignacio on a short leash.

Josh Mankiewicz: You understand how crazy that is?Ignacio Garraus: Yes.Josh Mankiewicz: Your wife does trust you. She shouldn't.Ignacio Garraus: Yes. It's correct.Josh Mankiewicz: The woman you're having an affair with doesn't trust you. But she should. You're cheating with her.Ignacio Garraus: Absolutely. She kept tabs on if any other women were showing interest in me.

Shawna was, he says, extorting sex from him, by threatening to tell his wife if he denied her. And if that sounds implausible, listen to this.

Josh Mankiewicz: I guess it's hard for me to believe that you could have sex with someone if you didn't want to because sex kind of requires the enthusiastic participation of the male.Ignacio Garraus: If I didn't perform, we would stay there until I performed. The quicker I performed, the sooner I could get home. Because she'd always drive.

Shawna Nelson was in a rocky marriage herself, and in July, 2005 -- roughly a year into her affair with Ignacio -- she made her lover a permanent part of her.

Ignacio Garraus: My family name tattooed to her leg. And I'm like, "You altered your body, yet we have-- you're-- you have a husband that you go home to. I have a wife that I go home to. Yet you put my name on your leg?"Josh Mankiewicz: That's like a neon sign saying, "run."Ignacio Garraus: I did. Then she got pregnant again. On the pill.

Pregnant, for the second time. Did anyone really think this was an accident?

Josh Mankiewicz: Forgive me, but by now why were you not using some kind of contraception?Ignacio Garraus: I wasn't allowed to use a condom to have sex with her.Josh Mankiewicz: So she was not only extorting sex out of you, she was extorting unprotected sex out of you?Ignacio Garraus: Yes.Josh Mankiewicz: And you went along with this?Ignacio Garraus: Let me tell you. I did. I had to do what she said … and then it came clear to me, "She's not on the pill. She's getting' pregnant on purpose."Josh Mankiewicz: I'm thinking people hearing this story might have figured that out--Ignacio Garraus: Yes.Josh Mankiewicz: --before you did?Ignacio Garraus: Yes. Yes. Did I approach this intelligently? No. Far from it. To know Shawna, you would not believe how she is. How strong-willed she is. How stone cold she is.

This time, the strong-willed Shawna decides there will be no second abortion. She's keeping Ignacio's love child.

Josh Mankiewicz: What do you think is going to happen when that baby is born?Ignacio Garraus: Oh, I'm just in neck deep. I literally sat and figured that I'm going to have to live for the rest of my life under her thumb.

If Ignacio's wife, Heather, knew nothing about the affair, she may have been the only person in town who lacked that knowledge.

Josh Mankiewicz: I guess the affair between Ignacio and Shawna was one of the worst kept secrets in Greeley.Jennifer Morrison: That would be accurate.

Jennifer Morrison was Shawna's supervisor at the county dispatch center, and says Shawna confided in her about the affair.

Jennifer Morrison: She told me that she was in love with Ig. That she loved him more than anyone else she'd ever met. And that she wanted to be with him, but that Heather stood in the way of that happening … She would talk about going to the shooting range and shooting at targets pretending they were Heather, to kind of, de-stress and vent her frustrations towards Heather.Josh Mankiewicz: Scare you?Jennifer Morrison: I remember when she told that, I thought, "Oh my god, this woman's got a gun. And knows how to use it."

And as in the movie "Fatal Attraction," it was a sign of what was to come.

Shawna was starting to focus her anger on Ignacio's wife, Heather.

"Shawna would tell me that Heather was a hag," says Jennifer Morrison.

Morrison was Shawna's supervisor at the police dispatch center.

Jennifer Morrison: Heather was "disgusting." She was "fat." She was "ugly." She was "demanding."

Morrison says Shawna's words and talk of the shooting range were frightening, and she reported it all to her superiors.

Ignacio says he could think of little else besides how to get Shawna out of his life.

Josh Mankiewicz, Dateline NBC: It doesn't sound like it's wrong to use the word obsession here.Ignacio Garraus: Oh, she's obsessed with me. Oh, yeah. Josh Mankiewicz: Warning signs?Ignacio Garraus: If I was to do something as a family, I couldn't say anything to her because she'd show up there.

If Ignacio took his family to a restaurant, Shawna and her family would be a couple of tables over. And apparently, Shawna even shared the same taste in movies.

Josh Mankiewicz: She's like stalking you?Ignacio Garraus: Yes.

But the affair continued, and Shawna documented much of it with her cell phone camera. Ignacio in uniform, in his car, with his dad. More than one image of Ignacio and Shawna together at a bar. Another shows the two literally in bed together. And a photo montage on Shawna's phone is titled "lovers."

Josh Mankiewicz: Three years? Three years this went on?Ignacio Garraus: Just about.Josh Mankiewicz: How can a man, how can you, a cop, be hostage like that--Ignacio Garraus: Oh, absolutely.Josh Mankiewicz: --for three years?Ignacio Garraus: I wish you could be in my shoes. Things developed. How subtleties developed.

What kept Ignacio from ending it? Fear? Inertia? Or, on some level, did he not want to stop? It was becoming more difficult by the day.

March 2006: Shawna gives birth to a healthy baby boy named Christian. That summer, a woman approaches Heather Garraus in public and tells her that baby Christian was fathered by Ignacio.

Josh Mankiewicz: And I'm sure Heather came home to you and said, "What about that?"Ignacio Garraus: And I lied.Josh Mankiewicz: What'd you say?Ignacio Garraus: The baby's not mine.Josh Mankiewicz: And she bought that?Ignacio Garraus: I think that her faith in me outweighed the denial aspect.Josh Mankiewicz: I mean, it's the punch line to a joke. "What are you going to believe, me or your own eyes?" And she believed you.Ignacio Garraus: Which is even that much more, you know, damning.

It was getting harder and harder for Heather to pretend to herself that nothing was going on.

Wendy Jones: They did less and less together throughout the years. And they'd been married 15 years, and she was probably thinking, "Well, you know, we're just at an-- you know…"Josh Mankiewicz: "This is what happens."Wendy Jones: This is what happens. And the signs are there, but you don't want to believe -- ever -- that your spouse is doing this to you.

But one evening in December, 2006, Ignacio cracks under the pressure. Heather wakes up in the middle of the night and her husband is gone -- because he sneaked out to see Shawna. When he gets home, Heather asks him what's going on. But this time, the lies stop. Ignacio confesses the affair.

Josh Mankiewicz: What'd you say?Ignacio Garraus: That "I had a three-year relationship with Shawna. It produced a child. And I know it's wrong. I'm sorry. But I'm glad you know. I know you always said," and I threw these words right at her. I said, "You always said you were going to divorce me, honey. I did. I screwed up. But I'm sorry."

Heather was crushed. Her worst suspicions were confirmed. But Ignacio felt a measure of relief.

Ignacio Garraus: It's almost like it was euphoric as having a weight lifted off of me, because having Shawna no longer have any type of power or leverage upon me was… You said I was emasculated? Well, I felt like a man again. Where I could be back in control of my own life.

Heather did what she had always promised. She left Ignacio -- for exactly one day. Then she returned, saying she wanted to work it out.

Ignacio Garraus: She goes, "Ig, I know you love me. I love you. There's no doubt in my heart that you have love for me Ig." Which I'm cringing, even that much more in guilt. And she goes, "I'm not going to divorce you, but you have to do these things.Josh Mankiewicz: And they were?Ignacio Garraus: An STD test. Go and see a psychologist or a counselor. And break it off with Shawna right then and there.Josh Mankiewicz: And you thought to yourself, what? I can do all that.Ignacio Garraus: I had my life back for a mere moment. I mean, as it's slipping through my hands. So whatever Heather wanted me to do, I would have done. And I did.

With Heather standing next to him, Ignacio called Shawna and broke it off. In the movie version of "Fatal Attraction," it's the wife who makes the call to the mistress.

Josh Mankiewicz: What did Shawna say when you called her and said, "I've told my wife. And you and I are done."Ignacio Garraus: Shawna somehow had Heather's cell phone. And a picture of the baby came up on Heather's cell phone. And below it was entitled, "Ig's flesh and blood." Sent to my wife's phone.

And that was just the beginning.

Another text to Ignacio: "You have no heart."

Another to Heather: "If you are reading this, you are a psycho bitch."

And this: "My loyalty is gone. I loved and trusted you and you f--ed me. Be prepared."

Ignacio and Heather thought they were prepared. But they were wrong.

Heather has forgiven Ignacio. He wants to make things right in his marriage.

Josh Mankiewicz, Dateline NBC: You really wanted to take your medicine?Ignacio Garraus: Yeah. Whatever it took, I was going to do. Because I had a chance, a grasp, a wisp of my life back.

He quickly agreed to Heather's terms: an STD test, counseling, and a quick end to the nearly three-year affair with Shawna.

That provoked a rash of angry, taunting text messages from Shawna, and then this voicemail.


It sounded like Shawna was going to sue to have Ignacio pay child support for Christian, the son he fathered during the affair with Shawna.

Ignacio, Heather and Victoria went to Florida over Christmas 2006, Heather called it a reset button for their marriage.

Ignacio Garraus: I have my girl back. All to myself. And life was good.Josh Mankiewicz: You got a second chance. You're describing a remarkably understanding woman.Ignacio Garraus: Yes.

When they returned to Greeley in January, 2007, their marriage was healthier but the threat from Shawna still loomed.

Ignacio and Heather moved Heather's car into their garage, worried that perhaps an angry Shawna might slash the tires. They also had their lawyer send Shawna a formal request to stay away from them.

Heather's sister, Wendy, and her best friend, Jayme, were getting the details from Heather about the scary emails and texts.

Wendy Jones: And then all of the emails stopped. And it was quiet. And I said, "This doesn't sound right, Heather.Josh Mankiewicz: The calm before the storm?Wendy Jones: That's how I felt.

On Jan. 16, 2007, came a final email from Shawna Nelson sent to Ignacio Garraus. It read in part: "I'm dead inside from all that has happened ... I wish you the best and hope you can be happy. I am now living every day in hell."

Whether or not that was true for Shawna Nelson, there can be no doubt that a life in hell was about to begin for Ignacio Garraus, a man who had an affair and couldn't end it soon enough.

In the film "Fatal Attraction," the mistress attacks the wife, but the wife kills her. This drama didn't have a happy ending.

It was Jan. 23, 2007, just after 6 p.m. It was dark in Greeley. Heather Garraus was leaving work when suddenly she was confronted by a person wearing a black robe and a black Halloween mask. Heather was ordered to her knees at gunpoint. Then the masked figure told her "You ruined my life," and then shot Heather twice in the head.

Ignacio was home when he got the call.

Ignacio Garraus: I left Victoria in the police car and I went flying into the trauma room. And then the doctor stops me at the door. I never saw Heather.Josh Mankiewicz: And the doctor says to you, what?Ignacio Garraus: "Heather's gone, Ig. Heather's gone."  For them to stop me at the door, I knew there was a reason they don't want me to see something.

Ignacio had to tell his 9-year-old daughter.

Ignacio Garraus: So I go and I pull Victoria from the patrol car. I go, "Victoria, mommy's dead." Imagine telling your kid that. So we sat there out in the cold, crying.

At the scene, one witness said the shooter ran like a woman. Another told police to look for Shawna Nelson. An APB went out on the radio, picked up by Shawna Nelson's husband Ken, whom you'll recall worked for the sheriff's department.

Less than 20 minutes after the shooting, Ken Nelson stopped his wife near their home, about seven miles from the crime scene. Another officer arrested her. But Ken Nelson wasn't done with this case, nor it with him.

Shawna was dressed in a black tracksuit. She was barefoot, but a pair of shoes with her DNA on them was found on a snow bank less than a 1,000 feet away. And a Halloween mask was found under the seat of the truck she was driving.

Police thought they had the killer. But did Shawna Nelson have help?

Josh Mankiewicz: When someone's wife dies-- you're a cop. The husband's always a suspect.Ignacio Garraus: Absolutely.

Ignacio Garraus and Shawna Nelson would meet once again, this time in a public courtroom.

Shawna Nelson: I did not do it. And I'm not going to stop fighting for people to hear that.

In February, 2008, opening statements began in the murder trial of Shawna Nelson, accused of killing Heather Garraus, the wife of Shawna's former lover, Ignacio. Shawna pleaded not guilty.

Ignacio Garraus had been questioned by police but eventually cleared. On the witness stand, prosecutors asked the same questions.

Prosecutors Cliff Riedel and Greg Lammons cut a deal with Shawna's former best friend, Michelle Moore, the woman who used to accompany Shawna when she taunted Heather Garraus in public.

On the stand, Michelle talked about how much Shawna hated Heather Garraus.

Michelle Moore: She had said that she wanted to get rid of her. Prosecutor: Was there any doubt in your mind what she meant?Michelle Moore: Not now … I guess, no, there's no doubt.

Michelle changed her story a few times, but ultimately admitted helping plan the murder -- although only Shawna was accused of carrying it out.

Cliff Riedel: Clearly, this is a case about an obsessive love that Shawna Nelson had towards Ignacio Garraus. And it ultimately resulted in the fatality of Heather Garraus. So, in a practical sense, there was a fatal attraction.

Shawna took the stand in her own defense, denying that she ever told Jennifer Morrison that she fantasized about killing Heather Garraus -- or that she actually did it.

Attorney: Did you have anything to do with the death of Heather? Shawna Nelson: No, I didn't. Attorney: Did you shoot her?Shawna Nelson: No.

Shawna says she was on her way to a liquor store around the time of the shooting. It wasn't the strongest alibi.

When they searched Shawna's home, police found a fully-drawn bathtub waiting for her, suggesting that perhaps she was planning to wash away any blood spatter after the shooting. In court, prosecutors used a life-sized mannequin made up to look the way they say Shawna Nelson appeared at the time of the shooting. Shawna says it was someone else behind that mask.

Attorney: Has drama taken place between you and Mr. Garraus, you and Heather Garraus?Shawna Nelson: Yes. Attorney: Ever have the desire to kill or shoot Heather over any of this?Shawna Nelson: Never.

The jury didn't believe her, and did what Ignacio couldn't do: put an end to Shawna Nelson's behavior, convicting her of first-degree murder. It took them only five hours.

Josh Mankiewicz: Ignacio Garraus likes to cast this story as one in which he was essentially held hostage in this affair. And then finally when it was over, when he finally did break it off with Shawna, he sort of didn't expect that Shawna would want to strike back at him. But she did. Is he right?Cliff Riedel: I don't know if he's right. I'm sure that that's how, in his mind, he wants to believe it happened … I'm not sure if an outsider would have the same view as Mr. Garraus does.Josh Mankiewicz: You think he could have gotten out if he wanted to.Cliff Riedel, prosecutor: Absolutely.

And in that, prosecutors are in agreement with Shawna Nelson's sister Deb Smith, who still believes Shawna is innocent of murder -- and that Ignacio Garraus wasn't helpless.

Josh Mankiewicz: Your sister's been described as this kind of vengeful, almost crazy woman who got hold of Ignacio and wouldn't let go, despite him repeatedly telling her, "I don't want to see you anymore." She just wouldn't give up.Deb Smith: Not true. A lot of people have believed that she's this monster. And it's not true. There was an affair. It did go back and forth. I think that there were times that she probably pursued Ignacio after they had ended it. There were times that he pursued her. Josh Mankiewicz: So what do you think of Ignacio?Deb Smith: He's a despicable man and I hope he's a better father than he is a person.

Greg Lammons, prosecutor: Ignacio Garraus is not the victim. Heather Garraus is the victim.Cliff Riedel, prosecutor: And Heather did nothing wrong.Greg Lammons: She had no affairs with anybody.Cliff Riedel: She's the only truly innocent person out of this. Or in the whole core group of folks.Josh Mankiewicz: The only one really on the side of the angels is Heather?Cliff Riedel: Yes.

And if this were a movie, there would be one more scene, a twist no one saw coming.

Imagine a flashback to the night of the shooting. It turns out that underneath that black robe Shawna is wearing are her husband's dirty clothes. She drives his truck to the credit ATM camera picks it up just before the shooting. When shell casings are recovered from the crime scene, they'll match her husband's gun. Shawna Nelson may have been planning more than just a murder.

Cliff Reidel: "I drive my husband's truck. I use my husband's service revolver. I wear my husband's underwear. I wear my husband's socks. I wear my husband's ball cap … I murder Ignacio's wife. If the police come looking, everything will point, physical evidence will point to my husband. If my husband gets accused of this murder. He's out of the picture. I have the children. Heather Garraus is deceased. Ig's available. We can all be one, big happy family."Josh Mankiewicz: That's diabolical.Cliff Riedel: And I believe the evidence shows Shawna Nelson was clearly diabolical.

In this fatal attraction, the wages of sin were truly death. It was his sin. But it wasn't his death.

Ignacio Garraus: I did the shallow thing. That my wife wouldn't be intimate with me, I would go find it somewhere else. So now I'm a shallow adulterer. I don't run from this.Josh Mankiewicz: You're ashamed of yourself?Ignacio Garraus: Oh yes. I loathe. And I got to hide it so my kid doesn't see how bad I loathe myself. Because a beautiful woman's dead for me having an affair, the chain of events that I had no way of foreseeing. But ultimately if I never had an affair, Heather would be alive. It's on me.

Shawna Nelson received a life sentence. Her former best friend, Michelle Moore, was sentenced to nine years for helping plan the murder. Both husbands have left law enforcement.