Transcript for The chilling true story behind 'Dirty John'
Reporter: It is the chilling tale of blind love. I was worried John would kill me to try to get the money. The papers show that he has numerous things, numerous social security numbers. Reporter: A handsome, volatile con man. He said I was a whore and a bitch and I was going to pay for what I did. Reporter: And a woman who fell for him. He got in my car, started it and set it on fire. Reporter: Setting in motion a chain of events with deadly consequences. Dirty John tells the story of John Meehan, a master of deception who charmed and tormented his unsuspecting victims, women like Debra Newell. What do you think when people hear your story and think how did you let this happen? I tell them you weren't in my shoes. Reporter: Millions listen to the podcast which has been adapted into a hit scripted bravo show. And now a new documentary from oxygen. In 2014, Debra had a successful interior design business, beautiful children and everything that money could buy here on the coast of Orange county, California. I decided I had it all except love. Reporter: That would change when she went online and met the man that would forever changer and her children's lives. I liked everything on his profile. His daughters, animals that he was an anesthesiologist. Reporter: She went on her first date with the tall, good-looking, self-proclaimed doctor at this Houston's restaurant. John started calling every day, and we would meet after work. And he started saying he was in love with me, I was the soulmate. He's been waiting for me. I ate it up. Reporter: Even though Debra had only known him for two months, she agreed to marry him while on a trip to Las Vegas. John seemed like the man of her dreams. What kind of things would he do? Everything. We would take walks at the end of the day, and he wanted to hear all about my day. He would make me breakfast, take my dry-cleaning in, take my mail to the mailbox. And I thought I have the perfect husband, I thought so. Reporter: The moved into this water front home on ritzy Balboa island. Overlooking red flag after red flag her children picked up from the beginning. What did they notice. The first thing they noticed is he didn't have a car. He was driving one of my cars. Reporter: But his story about serving with doctors without borders in Iraq was one of the tales in his story of deceit. Everything he told me was a lie. He was not a anesthesiologist. Reporter: John would isolate her. Everything came to a head. John was not who I married whatsoever. Reporter: It was his true nature, something his first wife of almost ten years, Tonya, is all to familiar with, sharing in the documentary how she learned I was a liar and drug addict. I found all the way to the back a box of anesthesia drugs. Reporter: He made violent threats in these phone calls. You enjoy your time left on this Earth, okay? Because that's what it's going to come down to. Reporter: Tonya and her daughter spentrs fearing for their lives. I always thought he was going to come and get us just to get back at my mom and I got scare. Someone that he has latched onto is never free from him. Reporter: She has learned about 50 victims made against John in 2013, arresting him after finding cyanide capsules, a gun and ammo. If we had not arrested him, something horrible would have happened to our victim. Reporter: He was released from prison in October of 2014. Two days later he met Debra and zeroed in. At what point did you start to realize something might be off here? Not until we were married. Reporter: It would take her more than a year to realize the full scope of John's due plisity. I said I'm leaving you, I want a divorce. Reporter: He stalked her, finding her car and setting it on fire. It was clear that this guy was really dangerous. Reporter: Did you ever think he would go after your children? I never thought he would go after my children. What did he have to gain? Reporter: But that's exactly what he did. John's reign of terror finally came to an end when he attacked her youngest daughter Tara outside her apartment building and she fought back, stabbing him to death in self-defense. For me, it was just surreal. Here's your daughter that fought for her life against someone you thought was the love of your life. Reporter: Now more than a year later, Tara is recovering and Debra is reflecting on her family's nightmare. What are the lessons that you learned from all this, that you hope other women can learn from you? Do the background. Really try to Fure out who this person is. Meet their friends. Never allow them to come to your home until you really know who they are. Take Reporter: Are these all things you wish you had done differently? Of course. Yeah. I let my heart lead instead of my head. Reporter: A life-threatening realization of how love can blind you from the dirty truth. How has it impacted your view on love? Are you dating? No. I'm not ready. Let's put it this way. I will do everything differently, and trusting the right person, yeah. Yeah, because there's good guys out there, too. Reporter: For "Nightline," Marci Gonzalez in Newport beach, California. Oxygen's documentary airs Monday night. And next, the actress breaking down barriers on
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