Father Amorth is a known Vatican Exorcist. He helps "Exorcist" director William Friedkin in his search to learn more about exorcism. Throughout the film, they discuss different aspects of the Catholic rite, and Father allows Friedkin to film an exorcism, an act not usually allowed by the Church. They film the 9th exorcism on an Italian woman called Christina. This seems to help her, and the family asks for the priest to bless her parents. This reveals that her seemingly cured possession may not have been as it seems.