I suppose what I had in mind was getting to play as the archetypal villain that the hero would traditionally try to defeat or escape from in a movie. Whether that's the only option or just one of them shouldn't really matter. Halloween and Texas Chainsaw Massacre would be perfect examples in that case.
Thanks for all the suggestions. I'll make sure I give you a mention.
I've noticed villain protagonists are ten a penny these days so hardly the novelty they were back then.