This is a truly chilling tale of the demonic possession of a girl, the mother who fights to save her, and the Catholic priest who risks his life to exorcise the demon. Regan is living in Washington DC with her famous mother. A series of poltergeist-like events occur in their rented house, after which Regan begins to undergo disturbing psychological and physical changes. Conventional medicine provides no relief so Regan’s mother, an atheist, turns to a local Jesuit priest, Father Damien Karras, for help. Father Damien is going through a crisis of faith but agrees to see Regan as a psychiatrist. After meeting Regan, now completely possessed by a diabolical presence, Father Damien asks permission to perform an exorcism. The church appoints a more experienced exorcist but allows Father Damien to assist. This is beyond a doubt the scariest book I’ve ever read. It’s very well written, rich, a thorough exploration of possession as defined by the Catholic Church.