The Last Exorcism (2010)

After years of gulling the faithful, cleric Cotton Marcus (Patrick Fabian) feels remorse and decides to expose his chicanery through filming a documentary. With a crew in tow, Marcus arrives at the Louisiana farm of devout Louis Sweetzer, who believes that his daughter, Nell, is possessed. When the usual stunts fail, he realizes that he is face-to-face with real evil and must summon true faith to protect Nell, the others and himself from demonic power.