A 1991 hidden-camera tape shows a woman walking up to a thin man in a gray T-shirt and asking if he remembers her. He was in the car with her sister the night the Zodiac Killer shot them both. The man was Mike Mageau. Around midnight on the Fourth of July, 1969, he and Darlene Ferrin, 22, were parked at Blue Rock Springs Park in Vallejo, California. A car pulled up behind them. A man walked over with a flashlight and opened fire without a word. Mageau, 19, was hit and lived. Darlene was dead by the time she reached the hospital. At 12:40 a.m. a man called Vallejo police. "I also killed those kids last year," he said. In the video below, you see Mageau 22 years later, and Darlene's sister Pam Huckaby, filmed through a fence as she asks him for one name. "There was a man that Darlene was very afraid of," she tells him. "I believe you know who he is." He says he doesn't remember a lot of names from back then. "You can't tell me you can't, Mike. I know you know who did it." A retired Vallejo detective tells the camera he never thought Mageau was telling the truth, whether out of some bigger involvement or just plain fear. That same year Mageau picked a photo out of a police lineup. "That's him! It's the man who shot me!" It was Arthur Leigh Allen, the only man police ever named as a suspect. Mageau admitted he never got a good look. "I'm not the Zodiac," Allen says on the tape. In 2002, DNA from the Zodiac's envelopes did not match him. The case is still open. Darlene's family never got a name. Did Mike Mageau know more than he ever said, or did he just never see the face that night?