"My dad and my mom had tried to have kids. She became pregnant but miscarried. And so… they wanted kids," Bruce Lisker tells "48 Hours Mystery" correspondent Erin Moriarty.
Then, one day, Bob came home and presented Dorka with a baby boy that one of his clients had put up for adoption.
"And she was like, 'What?'" Bruce laughs, "[She] was sort of thrown, but came to just love it. It was just a delight to her."
It was no surprise then that Bob and Dorka spoiled the child they named Bruce. There was the idyllic suburban childhood: Little League in the park and excursions to Disneyland and faraway places.
"I remember going to Hawaii Volcano National Park," Bruce recalls. "We just had a blast."
But the good times faded early. Bruce was only 11 when he began a long and destructive romance with drugs.
"By the time I was about 15, 16, I was smoking pot or drinking every day," he explains.
As Bruce's drug use escalated, his grades plummeted. His relationship with his mother got so bad and the screaming matches so upsetting, his parents finally made a tough decision and set him up in his own apartment nearby. Bruce dropped out of high school and surrounded himself with some tough characters, including Mike Ryan, a 15-year-old with a criminal record who bragged about getting into knife fights.
Bruce liked to think he was on his own, but says he was really just a spoiled kid whose parents were still taking care of him. "I was entirely subsidized by my parents. My mom shopped for me. She did everything."
All that would change forever one March morning in 1983. Bruce, who was just a few months from turning 18, says he started his day in typical fashion: "Got up, got stoned, got high. I smoked some pot… and then I had done some speed."
Around 11 a.m., he says, he drove from his apartment to his parents' house. "Whenever I would come over, my mom would come out on the front porch," Bruce says. "On that day, she didn't show up."
Bruce says when he knocked on the door, there was no answer.
"But I'm like, 'OK, I just want to go and see.' So I start walking around the house," he tells Moriarty. "I make my way to the living room window and I look as far as I can. And I thought I saw her feet. So I go to the next window, which is the dining room window, and I look in and… I could see the top of my mom's head. …she was on the floor."
Bruce says he searched for the hide-a-key, but it wasn't there. "And the last way that I knew to get in was the way that I had come in when I was a kid and I would miss curfew."
He says he entered the house through a window, but only after carefully removing the louver panes. Once inside, he made his way to the entry hall. "…and the scene that greeted me when I got to that final door was one that I don't wish on my worst enemies."
His mother lay sprawled on the floor, beaten almost beyond recognition.
"She was covered in blood. She had two knives sticking out of her back," he tells Moriarty. "She was unconscious… But she's heaving. She's breathing. She's alive."
Bruce pulled the two kitchen steak knives out of Dorka's back and then ran through the house, he says, to make sure the person who did this was not still there. Then he called for help.
Bruce: Help me, please! I need an ambulance right now! Hurry! My mom, she's been stabbed! She's been stabbed!
911 Operator: Quiet down…
Police arrived to find a hysterical teenager high on drugs and screaming to get the paramedics to rush his mother to the hospital.
Police subdued him. Bruce says, "They did a chokehold. They handcuffed me behind my back." They believed Bruce Lisker was not just a distraught son, but was his own mother's attacker.
"I mean, Bruce, here they have a young man who has said to people that he hated his mother, fought with his mother, was on drugs," Moriarty points out. "They get to the house and you've got blood on your hands. You're crazed. You're a pretty good suspect."
Bruce acknowledges, "I was somebody who needed to be looked at. I was somebody who needed to be talked to."
At the police station, Det. Andrew Monsue listened to Bruce's story, and then told him it was nothing but lies from beginning to end.
"He said, 'Well, none of that fits. None of that works… You're lying. I think you did somethin' to your mom.' And I'm like, 'This nightmare just got worse.'"
Bruce's father arrived from the hospital and told Bruce his mother had died. Then Bob Lisker asked the detective when he could take his son home.
"Detective Monsue said, 'Oh, he's not going home. He's under arrest. You can come see him at Sylmar Juvenile Hall.' And he was silent, was silent. He didn't even know what to say," Bruce recalls of his father's reaction.
Bruce swore he was innocent. He and his father urged police to look into his troubled friend, Mike Ryan, who had gone to the house to see Bruce's mother the day before. But Det. Monsue was focused on Bruce as the killer. And he was ready to hand the prosecutor an open-and-shut case.