When a young girl is possessed by a demon, a pair of Catholic priests struggle to exorcise the evil spirit while suffering doubt in their own faith. Based on a 1971 novel by William Peter Blatty, this 1973 horror movie stunned audiences not with over-the-top gore or shocking violence but with a pervasive sense of dread, the corruption of innocence and a realistic style that hinted at true horrors lurking in our everyday lives.
It might seem strange to call "The Exorcist" a subtle horror film, since it does have scenes of a girl's head spinning around and projectile puking. But it wasn't the lurid shocks that left such a lasting impression. It was the way "The Exorcist" incorporated Judeo-Christian mythology of demonic spirits and a very literal battle between good and evil that made waves [source: Truitt]. Billy Graham proclaimed that the movie itself was possessed by a demon, and some towns in Britain banned the movie [source: Larnick]. "The Exorcist" was so dark that there's a persistent legend that production of the movie was cursed.
The movie's success created high demand for more horror focused on "Christians versus demons." A number of prequels and sequels followed, along with "The Omen" series and more modern possession flicks like "The Possession," "The Exorcism of Emily Rose" and "The Last Exorcism." Roman Polanski's "Rosemary's Baby" came out five years before "The Exorcist" and focuses on similar themes, but it was the astonishing box office success of "The Exorcist" that changed horror.