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 investigating 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...