Movie: Sleepaway Camp (1983)
Writer: Robert Hitzik and Marshall Brikman

Sleepaway Camp is the kind of batshit horror flick that could only come from a year predating 1990. On the surface, it's your run-of-the-mill slasher movie, with a group of unlucky, and mostly horny, campers and counselors getting sliced and diced by a mysterious killer. The motive traces back to eight years prior, when protagonist Angela's (Felissa Rose) brother Peter, their father, and his gay lover were, apparently, murdered in a boating accident.

Or so you're supposed to believe. In the film's genuinely holy-shit finale, Angela's pants drop and all of her manhood is shown, because, get this, Angela is actually Peter, who, years before, underwent a transgender switch. And as if that reveal isn't bonkers enough, long-haired and trouser-less Peter lets out a strange, highly disturbing “hiss” sound while coldly staring and resembling a cardboard cutout of a pint-sized Cro-Magnon caveman.

Yeah, Hollywood isn't about to do a shot-for-shot remake of Sleepaway Camp anytime soon.