When “The Dating Game” host Jim Lange introduced Rodney Alcala as Bachelor Number One, a successful photographer, he didn’t know that the man had already murdered at least five women and been charged with the attempted murder of a little girl.

Alcala has since been convicted of killing seven women in the 1970s. He was charged with murder for the first time in 1979 for the death of 12-year-old Robin Samsoe, who disappeared in June that year on her way to a ballet studio. Her remains were found nearly two weeks later in the San Gabriel Mountains north of Los Angeles.

“The ‘Dating Game’ appearance is just a bizarre part about this case,” said Matt Murphy, an ABC News contributor and former prosecutor who was assigned to Alcala’s case in 2003. “And I think that what it reflects is the narcissism and the ego and the arrogance of a serial killer.”