Transcript for Could This Woman Be Living With a Killer?
Tonight, the stunning case thrust into the national spotlight, two wives, one dead and one alive. Murder investigation that had reached a dead end until "20/20" got on the case. Tonight, the bombshell tonight. Tonight, we take you from the courtroom to the crime scene to the bedroom and to something sitting on the bedside table and a clue buried with the wife -- until now. You'll see the video recorded by the murder suspect himself, would his own words haunt him? John Quinones back on the case that he broke wide open. Reporter: In the heart of Utah's Salt Lake valley single mom Vanessa pond raises her 11-year-old daughter. The only man she can depend on is her father, and he says, she's fine with that. I used to jokingly refer to her as the president of the man hater's club. Reporter: That is until this man, raven abaroa, a good-looking 28-year-old widower chats her up at their children's school. She agrees to have lunch. What was it about him that you liked? He seemed very upfront, very honest and genuine. I found that, you know, he was a single father. And I really, really admired that. I'd been a single mom for five years. I know what it takes to raise a child. I thought, you know, maybe I'll give him a chance. Reporter: Vanessa and raven were both raised Mormon and she felt she could take raven and his son Kaiden under her wing. Did he mention his ex-wife? What happened to her? Yes. As we were just starting to date, he just mentioned that, "My wife actually died." I immediately felt so sorry for him. He said that there was an intruder and that she was killed. And that he'd found her. And he had left it at that. Reporter: But Vanessa can't put her curiosity aside about raven's first wife. She goes online to find out more. Breaking story right now. Janet abaroa murdered. No one has been ruled out a suspect. That night I stayed up until about 4:00 in the morning Reading blogs, watching his interviews, Reading all the news stories about it. And going out of my mind. Reporter: Thinking what? I wasn't convinced that he was innocent. Reporter: And watching a local TV interview taped after his wife's death doesn't help. Janet died that night. I remember watching the interview and I wasn't convinced. In the interview, they asked him, you know, what he saw, what he came home to. I don't like talking about what happened to her and it's not because I don't love her and it's not because I don't want to find out who did it, it's because I have so many good memories with her that, you know, I hate thinking about the bad times. So, I went over and -- I spoke with him, asked him the questions that I had and he removed any and every doubt from my mind. He had his stories about how people were trying to frame him. About how horrible the cops were. Reporter: Vanessa becomes convinced that raven isn't responsible for his wife's murder. Now, he would try to persuade her to start a life with him. He started talking about me moving in after probably just a few weeks. And that was very, very fast for me, and I told him that I wouldn't be moving in with anybody if I wasn't at least engaged to them, knowing that I'm going to spend the rest of my life with them. Reporter: Were you worried that this might be a mistake? I didn't have a question in my mind at the time. Reporter: But Vanessa's father, a former police officer does. He has a cop's hunch and a father's instinct. The Christian side of me wants to believe that he is innocent until proven guilty. The police officer side of me says there is something wrong with this picture somewhere. Reporter: Raven is summoned to an awkward face-to-face meeting with Vanessa's parents. They asked him if he had had anything to do with his wife's death. And his response was -- well, he kind of sidestepped the question and he didn't say, "Yes, I did it" or "No, I didn't do it." He said, "I loved my wife. I loved her so much." Which insinuates that he didn't do it. But he didn't come right out and say that he didn't. He was in tears, and Vanessa went over and put her arm around him to console him and comfort him. She says, "No, I know the guy by now and I am really convinced that he's -- he is not guilty of this." At the end of it, they still had their reservations, but soon after that, raven asked my dad for my hand in marriage. Reporter: Vanessa and raven are married in her parents' backyard. It would be a blended family -- his 7-year-old son and her 6-year-old daughter. Vanessa's mom gives her a kiss, and gives raven a message. Just take good care of my little girl. He promised me he would. Reporter: A honeymoon in las Vegas follows and raven tells his bride something that still makes her shudder to this day. He started talking about Janet and how mad he was after she died. Not how sad. Not how heartbroken. Just mad. Reporter: At whom? Just that she was dead. And then he cuddled up closer to me, and he said, "I promise I'll never hurt you." I didn't know what to think about that. Or, how to feel about that. It scared me. Reporter: And that's not all that scares her. Even before the honeymoon is over, an outburst from nowhere. Within moments he could switch, he could say the most horrible things. I was an Where, a lot. And then moments later he would apologize, "I'm sorry. I was just mad." "That's just what I say when I'm mad. That's just what I do." Reporter: Then, Vanessa says, raven's mood swings become physical. He grabbed me from the door and threw me up against the wall and then I fell. Later, he tried to convince me that I had tripped. He began to call my own family, and my own friends, telling them that I was horribly depressed and bipolar and that I probably needed to be institutionalized. Reporter: Just four months into their marriage, Vanessa becomes more and more frightened for her safety and begins to make plans to leave. But it's Christmas eve, a time when her family traditionally gets together. And as she and raven get ready to go to her parents' house for dinner, another incident of unprovoked violence. He had me backed into the corner and he was screaming at me, and poking me in the chest, just yelling at me. I ended up with bruises on my chest from him. He started gathering his things and I wasn't going to stop him. And that fueled his fire. Reporter: Vanessa believes raven is trying to set her up, building another narrative that she is unstable. Could he be hatching a plan? I think he was in the process of setting it up, with family, and friends, that I'm suicidal. After seeing the jekyll and Hyde that I lived with, his eyes would just change. It was very scary. Reporter: Vanessa has no idea how much raven abaroa was more sinister Hyde than Dr. Jekyll. These six women are desperate to warn her. He's a dangerous person. We were fearful for her.
This transcript has been automatically generated and may not be 100% accurate.