Regan McNeill is a young girl living with her actress mother in a suburb of Washington DC. She begins to exhibit strange behaviour after she starts playing with an Ouija bord. Her mother, Chris, seeks the help of medical professionals, but they are unable to explain the radical changes. Symptoms such as violent convulsions and a deep, menacing voice suggest something far more sinister than mere illness.
Desperate for answers, Chris turns to Father Karras, a Jesuit priest and psychiatrist who is grappling with his own crisis of faith after the death of his mother. Karras initially approaches the situation with skepticism but becomes increasingly convinced that Regan’s affliction is a case of demonic possession. With the help of the more experienced Father Merrin, the two priests perform a difficult exorcism.
The battle of wills against the demon Pazuzu is beset with severe physical and psychological horrors that challenge the faith and strength of the Jesuits. This forms the climax of the book.
A recurring theme of the book is the nature of evil and the meaning of faith, both absolute and personal. The writing style makes the reader also experience the profound psychological horror that challenges the primary characters. Excellent writing, with a gloomy gothic feel to the whole narrative add to the sinister and eerie feeling. An absolute must read.