13. The Last House on the Left (1972)
Director: Wes Craven
Based loosely on Ingmar Bergman’s The Virgin Spring, The Last House on the Left is an exploitation horror film that is notorious for the rape/torture scenes that fill out the film’s second act. In fact, the movie was found to be so sadistic and unseemly that it was banned in Great Britain for a while because of the unrestrained violence and sexual humiliation that run rampant throughout.
There's one scene in particular that should have men everywhere reaching for the Pepto Bismol, when, in a twisted act of revenge, the mother of the rape victim proceeds to orally remove the manhood of the perpetrator that killed her daughter. This revenge-fantasy was Wes Craven’s first feature-length directing gig, and it went on to redefine the horror genre. Don’t bother with the recent remake; if you want to be truly disturbed, go for the raw, deplorable original.