Young priest O Su-min belongs to a religious organization that unofficially conducts exorcism rites. He is still tormented by guilt over not being able to save his mother from death in the past, a mother who was possessed by evil spirits. He meets a young idealistic doctor, Kham Yn-ho, who does not believe in higher powers or the supernatural. The girl becomes a witness to supernatural phenomena, and major changes begin to take place in her life.