10 Great Horror Movies Ruined By Their Twists
5. Sinister (2012)
It is admittedly very difficult to stick the ending to a horror movie. It's much easier to build suspense with creaking doors and dancing shadows than it is to pay it off with coherent revelations regarding the villain's motivations (see Mama, Insidious, etc.). That being said, oy vey does Sinister flub it.
Ethan Hawke plays Ellison Oswalt, a true-crime author who moves his family into a house with a violent past. Freaky stuff starts going down and eventually the Oswalts are forced to move out of the home in an attempt to leave the freakiness behind them forever. Then comes a reveal that makes no sense at all within the diagesis of the film: the family's being tormented by the demon are only murdered AFTER they move out of the house where the torment was occurring.
This works as a good twist to cue the audience in to the fact that some family-murder is about to go down, but nothing is mentioned as to why an ancient demon would be inclined to do it that way. Add this to the relatively weak climax (and wholly silly child-abduction) and you're all but guaranteed to leave with no recollection of the good parts.