"We always had to make a conscious decision to make the same movie over again, only each one would be slightly different," says Steve Miner, the director of the second and third Friday the 13th installments (and associate producer of the first), in the franchise's oral history, Crystal Lake Memories. Indeed, by 1982's Friday the 13th Part III, the series was already repeating itself: once again, we watched a formerly bullied giant mama's boy stalking dumb kids in a rural setting, killing some in ways he had killed their predecessors (through-the-bed stabbing from below got a reprise). The climax virtually repeated that of the first film's except it was Jason who was doing the slaying and his now-decomposing mother who did the final-scare popping out of the water. They just traded roles, of course — shifting bodies around was business as usual.

Roman Polanski's 1968 film Rosemary's Baby was among the earliest examples of the modern, post-Universal monsters phase of horror cinema, and yet it remains among the genre's most mature, least conventional offerings. A key factor in its endurance is described in David Konow's recent chronicle of horror's history, Reel Terror: