William Peter Blatty On Thursday author William Peter Blatty, best known for writing "The Exorcist," passed away at the age of 89 at a hospital in Bethesda, Maryland. Blatty was a former Jesuit school valedictorian whose novel about demonic possession terrified millions both in print and on the screen. Inspired by an incident in a Washington suburb that he had read about while in college, Blatty's "The Exorcist" was published in 1971, followed two years later by the film of the same name. Blatty won an Academy Award for the screenplay, and even went on to write and direct a sequel "The Exorcist III." Blatty's widow, Julie Alicia Blatty, told the Associated Press that the cause of the author's death was multiple myeloma, a form of blood cancer.