Every generation gets the evil-kid movie it deserves, with past standouts such as The Bad Seed, The Exorcist, and David Cronenberg's The Brood all handily serving to exploit a parent's worst fear while simultaneously offering up a bit of subliminal reassurance. (So your kid spilled Juicy Juice on the couch, you say? Call us when her head starts swiveling all the way around.) Orphan may not be the defining child horror film of its era (that honor still belongs to 2007's brilliantly subversive Joshua), but it carries a squicky, exploitative charge that leaves most big-studio horror in the dust. Boasting a pair of far-beyond-the-call performances by Peter Sarsgaard and Joshua vet Vera Farmiga, it sets up a series of increasingly queasy taboo points and then proceeds to rocket-cycle over them.

You've seen the trailer by now: Grieving from a recent loss, a pair of casually upper-class folks adopt the mysterious, Russian-accented Esther (Isabelle Furhman). It doesn't really work out. Director Jaume Collet-Serra, previously responsible for the not-remotely-as-sucky-as-it-probably-should-have-been House of Wax revamp, handles things with a fair amount of aplomb, finding a balance between creepy character-building downtime and some unusually ferocious Dolbyfied money shots. (However, 123 minutes is still an awfully long time for this sort of thing.)

Ruthlessly effective as it is, though, Orphan would likely slide handily out of the short-term memory and into B-movie Cinemax limbo were it not for the final act, which contains one of the most hysterical, loopy, pure-D bugfuck plot developments in the history of the genre. (Do yourself a favor and stay far away from IMDB until catching a matinee.) Call it crass, call it ridiculous, but when a movie can make an entire audience laugh and gag at the same time, something's cooking.