THE EXORCIST
When young Regan starts acting odd, levitating, speaking in tongues, her worried mother seeks medical help, only to hit a dead end. A local priest, however, thinks the girl may be seized by the devil. The priest makes a request to perform an exorcism, and the church sends in an expert to help with the difficult job.

EXORCIST II: THE HERETIC
Owing to his experience with exorcisms, Father Lamont is chosen by his superiors to investigate the death of Father Merrin, who died during the exorcism of young Regan MacNeil. Lamont finds Regan under the psychiatric care of Dr. Tuskin. By hypnotizing the girl, he is able to learn that Merrin previously exorcised the same demon from a boy in Africa. Hoping for answers, Lamont travels to Africa in search of the youth.

THE EXORCIST III
Police Lt. Kinderman notices similarities between his current murder investigation and the methods used by the "Gemini" killer who was executed 15 years before. He soon discovers a hospitalized mental patient claiming to be the dead serial killer, but who looks uncannily like a priest Kinderman knew who died during an exorcism. As more bodies are found, Kinderman looks for connections between the two supposedly dead men.

EXORCIST: THE BEGINNING
Father Merrin is haunted by his experiences in World War II, when occupying Nazi troops forced him to be complicit in their atrocities. In the aftermath, he has renounced his faith and begun working as an archaeologist. He travels to Kenya, where a fifth-century Byzantine church holds ancient relics. There he encounters Sarah, a doctor and concentration camp survivor. The strange occurrences that soon begin reunite him with the evil he sought to escape.

DOMINION: PREQUEL TO THE EXORCIST
Haunted by terrible acts the Nazis forced him to participate in, the disenchanted Father Lankester Merrin focuses his energies on helping with an archaeological dig in the northern part of Kenya. There, the crew uncovers a church that predates Christian missions into the area, but the discovery also causes strange events to start occurring, including physical changes to a young, disabled boy, whom Merrin grows to suspect has been possessed by a demon.