The winners: Fortunately, producers of the show told CNN that the pair never went on a date

With his trademark long hair cascading onto  his over-sized disco shirt collar, serial  killer Rodney Alcala's answers are  charming, funny and steeped in cheeky innuendo.

Indeed, the handsome 35-year-old makes light  work of convincing the pretty contestant behind the screen to pick him as  they appear on hit 1970s game show The Dating Game.

But unbeknown to her, the show's producers  and the millions of viewers tuned in at home, the smiling photographer had  already murdered two women and would go on to rape and mutilate four more and a  12-year-old girl.

And in a moment of spine-chilling foreboding,  Alcala clinches the show by telling her: 'We're going to have a great time  together, Cheryl.'

It was this appearance in 1978, unearthed by CNN, that would  earn him the moniker, 'The Dating Game Killer'.

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