Before he was a convicted serial killer, Rodney Alcala was a winning bachelor on "The Dating Game."
"Oh yeah, I remember it quite clearly," said Jed Mills, the contestant who sat next to him. "He was creepy. Definitely creepy."
Found guilty in Southern California in February of murdering four women and a child, Alcala, 66, is acting as his own attorney in the penalty phase of the trial. He is hoping to convince the jury to spare his life.
The crimes he committed date back to the late 1970s. Nobody at the time knew the man with the wavy long hair and toothy grin was a psychopath.
That includes Mills, a veteran television and film actor, whose only encounter with Alcala was when both of them appeared as bachelors on "The Dating Game." "That's when I became part of a nightmare and I didn't realize it was a nightmare until 32 years later," Mills said.
The now infamous episode aired in 1978. Alcala, who already had been for the 1968 rape of an eight-year-old girl, was the first contestant to be introduced by the host.
"Bachelor number one is a successful photographer who got his start when his father found him in the dark room at the age of 13 fully developed," Jim Lange bellowed to the camera. "Between takes you might find him skydiving or motor-cycling. Please welcome Rodney Alcala."
After the three bachelors were announced, the young woman who would choose one of them for a date began asking questions. She posed her first one to Alcala.
"What's your best time?" she said.
The best time is at night," Alcala answered with a wide smile. "Night time."
Mills, who was the center bachelor, said he had an almost immediate aversion to Alcala. "Something about him, I could not be near him," Mills recalled. "I am kind of bending toward the other guy.to get away from him and I don't know if I did that consciously but thinking back on that I probably did."
But Alcala was able to charm Cheryl Bradshaw from the other side of the Dating Game wall. ""Who will it be?" the host asked her at the end of the show. "I'll take One," Bradshaw replied and out strolled Alcala as the winning bachelor.
If Alcala appeared likable to viewers at home, Mills said he was the complete opposite when they sat together in the show's Green Room.
"He was quiet but at the same time he would interrupt and impose when he felt like it" Mills said. "And he was very obnoxious and creepy – he became very unlikable and rude and imposing as though he was trying to intimidate. I wound up not only not liking this guy but not wanting to be near him..he got creepier and more negative. He was a standout creepy guy in my life."
Within months of his "Dating Game" appearance, Alcala would become a killer, abducting and murdering a 12-year-old girl in 1979. Before the decade was over, Alcala would claim four more victims.
CNN asked noted crime profiler Pat Brown to analyze Alcala's appearance on "The Dating Game."
"He was aware that he could say things. that were considered sexy and funny and the girl would like that," Brown told CNN. "He watched the game and he gave those answers and he won, so he learned some tricks. But a psychopath's true nature comes seeping through.
"When you go back and look, what's most fascinating is that he had already committed a crime," Brown said, "Raped a little girl. Here is a man portraying himself as a desirable young man when he is a violent sexual predator of children."
Alcala's real identity revealed itself off the stage when he was with the other bachelors, Brown believes.
"He is showing his psychopathic personality in the Green Room," she said. "He wasn't acting at that time, those were his enemies and he had to beat them to get the girl and he wanted to win.
"This guy probably literally hated them. This guy was going on the show to prove how special and wonderful he was. And his ego was riding on it."
Though Bradshaw chose Alcala as her date, she refused to go out with him, according to published reports. Being rejected can have a profound impact on serial killers, Brown suggested.
"One wonders what that did in his mind," Brown said. "That is something he would not take too well. They don't understand the rejection. They think that something is wrong with that girl. She played me. She played hard to get."
Jed Mills said he still has a difficult time discussing Rodney Alcala.
The more time has gone by, the creepier it gets," he said, "because it kind of sinks in slowly. What this guy did, it's hard to express. He kind of haunts me a bit.
"Just talking about it I get a tightness in my stomach."
For more crime coverage go to cnn.com/crime.