Transcript for Woman who killed 'Dirty John' says she channeled 'Walking Dead' during attack
away and the police. Someone has been stabbed and he attacked a girl. Reporter: It is just after 5:00 P.M. And Tara has just heroically saved her own life by stabbing her stepfather 13 times. Her hulking assailant, John plea Han, the man infamously known as dirty John. Her mother's estrankd husband who terrorized and stalk their family. He attacked her in this parking lot, knife in hand. He looks me in the eyes and says, do you remember me? Terry realizes she is in a fight for her life. I started trying to get away from him. He keeps grabbing me. At this point stabbing me but I'm not aware that he's stabbing me because the knife is in a del taco bag. I think he is punching me. We fall down and he is on his knees. And I'm on my back and I'm pedal kicking his forearms as he was trying to come down and stabbed me. She has an inch deep stab wound. The knife lands in that position. I pick it up and I just start whaling back on him. She flashes to her favorite show, the walking dead. I'm pushing him off me but I'm holding his head. Because watch the walking dead and I don't want him to bite me. That's what you were thinking. Yeah. And I thought, I don't want him to wake up and just try hurt me again because I think he'll try to kill me again. So did I the second to last one here and then the last one was in the eye. That's the softest point of entry. So I wanted to kill his brain like a zombie, essentially. Neighbors rush over to help. I told my mom to call 911 and say that somebody was being stabbed. Newport beach 911. There is a man and a girl screaming. When they arrive, John is near death. Ending a nightmare that has engulfed her family for nearly two years. First chronicled in the "Los Angeles times" podcast called dirty John. Is there something about John's past he's trying to hide? Which was then put into a bravo show starring Connie Briton and Eric banna. And a documentary from oxygen. Dirty John, the dirty truth. You enjoy your time left on this Earth. I thought he would hurt her, my sister or me. But I always had the sense that it was going to be me for some reason. That eerie hunch started in 2014. Soon after Tara's mother, Deborah Newell, a successful interior designer met John online. She said I liked everything on his profile. He had his daughters, he had animals. He was an anesthesiologist. The then 59-year-old went on her first date with a tall, good looking doctor. He started calling every day and we would meet after work. He started saying he was in love with me. I was the soul mate. He's been waiting for me. I ate it up. Tara was initially optimistic that maybe this relationship would last. We were on the phone and she was just telling me. I met a great guy. Oh, well, I would love to meet him. But when she did, she instantly got a bad feeling about him. The first time I met him, he's not that warm. Even though Deborah had only known John for two months, she agreed to marry him while on a trip to Las Vegas. He seemed like the man of her dreams. We would take walks at the end of the day. He wanted to hear all about my day. So you thought I've got the perfect husband. I thought so. They moved into this water front home on ritzy Balboa island. She paid for everything. Overlooking red nag after red flag, her children picked up on from the beginning. Well, my sister was telling me, there is something not right with him. He says he's an anesthesiologist. He's driving around my mom's car. He says all of his stuff got stolen. John said his car was stolen while he was serving in Iraq with doctors without borders. But that was just one fictional tale in a web he was setting. Almost everything was a lie. He tried to isolate her from her children to control every aspect of her life and wealth. He accused me of trying to separate my mom from him, saying that I wanted my mom because I wanted her money. He would stop at nothing to get what he wanted. He would send my sister text tens but from my mom's phone pretending to be my mom and telling my sister she should kill herself. Your sister thought they were coming from your mother? At first she did, yeah. Then I looked at it and I said our mom doesn't talk like this. But Deborah was still under John's spell? He had an excuse for her for everything. She was brainwashed. Yes. She didn't realize how much danger she was in. He was the most evil person I've ever met. The stalking allegations made by another woman in 2013. She said she's learned of at least 50 victims since. Someone he is latched on to is never free of him. The detective arrested him after finding cyanide capsules, a gun, and ammo he had stashed. If we had not arrested him, something horrible would have happened. He was released from prison and two days later he met Deborah and zeroed in. It would take more than a 84 before Deborah realized the scope of the duplicity after she uncovered his history of tormenting dozen of other women. She hid away for good. Hiding for months. Still, he stalked her. Finding her car and setting it on fire. When he set fire to my mom's car, I was hoping he might get arrested and we hoped we wouldn't have to deal with him anymore. He called my work and made an appointment. He did a fake French accident. I was thinking, this sounds weird. One day later he made his move in that parking lot. Someone has been stabbed and he attacked a girl. I was so angry when they did that. This guy just tried to kill me. And if he is able to survive by any chance, then he will still try to kill us. I know he's going to kill me! Deborah frantically arrives at the scene. My daughter! Hang on. John is rushed to a hospital where he dies four days later. After the attack, Tara is flooded with an array of extreme emotions. I felt guilty after all of this, right? I did. Why? I thought he can have a family. He can have someone that cares about him and I don't want the people who loved him to feel bad. But she's reassured by John's sisters, ex-wife and daughters. Did anyone thank you? His ex-wife. She said thank you? Uh-huh she knows it would have been her next. And what's next for Tara and her mom. It was hard. It was her husband. Do you forgive her? You know, I forgive her but I don't forgive him fully? I like him. She's a lot more cautious. Same bubbly personality. But cautious. Tara is working on herself, too. She wrote a book talking about her ongoing struggles with trauma. I definitely struggle with PTSD. I have good days and really bad days. So what kind of days are still tough for you? Sometimes loud noises. And those sometimes get to me. And sometimes when someone touches me abruptly, that can be triggering. She said with the wild popularity of her family's real life saga, she now gets recognized in public but said she is proud to share what she survived. I feel like this experience has changed me. In such positive ways. For "Nightline" in los Angeles. Oxygen's documentary dirty John, the dirty truth, is available on demand.
This transcript has been automatically generated and may not be 100% accurate.