Pazuzu (The Exorcist) to take complete control of her mind. However, with the aid of the priest Father Tomas and her family, Regan fights back against Pazuzu, regaining control of her mind, just as Father Tomas exorcises the demon from her body. William Peter Blatty's creations of Pazuzu and "The Exorcist" were based on a heavily reported series of 1949 events in St. Louis, Missouri concerning the possession of a 14-year-old known as "Robbie Mannheim" (or sometimes "Roland Doe"). Blatty, who was a student at Georgetown University, read about the story in Washington, D.C. newspapers and created "The Exorcist" twenty years later. In
The Exorcist III film), as the protagonist. Blatty conceived "Legion" as a feature film with William Friedkin, director of "The Exorcist", attached to direct. Despite the critical and commercial failure of the previous sequel, Warner Bros. was keen to proceed with Blatty and Friedkin's plans for another "Exorcist" film. Blatty said that "everybody wanted "Exorcist III"... I hadn't written the script, but I had the story in my head...and Billy [Friedkin] loved it." Friedkin, however, soon left the project due to conflicting opinions between him and Blatty on the film. The project went into development hell, and Blatty wrote "Legion" as a novel