愁云惨淡的华盛顿市，一幢普通公寓内，单身妈妈克莉丝（艾伦·鲍斯汀 Ellen Burstyn 饰）和女儿芮根生活于此。然而近一段时间，克莉丝却被女儿种种怪异的举止折磨得烦躁不堪。芮根的行为举止怪异，迥异常人。克莉丝带她求医问卜，终无所获，甚至精神科医生也束手无策。万般无 奈之下，几近绝望的母亲求助于莫林神父（马克斯·冯·西多 Max von Sydow 饰），一个有着丰富驱魔经验的老者。恐怖的夜晚，神父与藏身少女体内的恶魔展开连番较量。这是一个注定让无数人永生难忘的恶魔之夜…… 　　本片由William Batty根据1949年一起真实的驱魔事件创作的小说改编，荣获奥斯卡金像奖最佳混音奖和最佳改编剧本奖。A visiting actress in Washington, D.C., notices dramatic and dangerous changes in the behavior and physical make-up of her 12-year-old daughter. Meanwhile, a young priest at nearby Georgetown University begins to doubt his faith while dealing with his mother's terminal sickness. And, book-ending the story, a frail, elderly priest recognizes the necessity for a show-down with an old demonic enemy.