Exorcist II: The Heretic is a 1977 American horror film and the sequel to The Exorcist. It was directed by John Boorman who also co-wrote the screenplay with William Goodhart from an original story by Rospo Pallenberg. The author of the original, William Peter Blatty was not involved in the production, and received credit only for creation of the characters.
Richard Burton stars as exorcist Father Philip Lamont in John Boorman's sequel to The Exorcist. The cleric, who is struggling with his faith, is assigned by the Archbishop investigate the death of Father Merrin (Max Von Sydow), who was killed in the course of exorcising the Assyrian demon Pazuzu from Regan MacNeil (Linda Blair). Although now seemingly normal, Regan continues to be monitored at a psychiatric institute by Dr. Gene Tuskin (Louise Fletcher). In an attempt to plumb her memories of exorcism, Dr. Tuskin has hypnotized the girl, to whom she's linked by a "synchronizer" and is so overcome by "witnessing" Regan's memory of the event that Lamont has to rescue her. After a tour of the Georgetown house where the exorcism took place, Lamont returns to be coupled with Regan by synchronizer. The priest is spirited to the past by Pazuzu to observe Father Merrin exorcising a young boy, Kokumo (Joey Green), in Africa. Learning that the boy developed special powers to fight Pazuzu, who appears as a swarm of locusts, Lamont journeys to Africa, defying his superior, to seek help from the adult Kokumo (James Earl Jones).
Exorcist II: The Heretic was one of the biggest flops in motion picture history. Literally laughed off the screen at its premiere, the film was hastily pulled from release and quickly recut by Boorman in a vain effort to salvage it. The revised version fared no better (Boormans restructuring serving chiefly to make the film even more incomprehensible) and was the only version of the film avaliable for many years, until the release on videocassette of the original cut in the early 1990's. The film greatly damaged the careers of all involved, with Blair in particular going from the enviable position of one of Hollywood's hottest young actresses to being relegated to a future in low-budget exploitation films.
Boorman would recover with the superb Excalibur a few years later, and the Exorcist series finally got a worthy sequel in 1990's The Exorcist III, adapted by William Peter Blatty from his own novel Legion. Blatty's film serves as the true sequel to the original, ignoring the events of Boorman's film, much as the general public had a few years before.