The screeching strings, the plunging knife, the slow zoom out from a lifeless eyeball: in 1960, Alfred Hitchcock's Psycho changed film history forever with its taboo-shattering shower scene. With 78 camera set-ups and 52 edits over the course of three minutes, Psycho redefined screen violence, set the stage for decades of slasher films to come, and introduced a new element of danger to the movie going experience.