“Exorcist II: The Heretic” is a horror film released in 1977, directed by John Boorman and starring Linda Blair, Richard Burton, and Louise Fletcher. It is the sequel to the 1973 film “The Exorcist,” which was a critical and commercial success.

The film follows Regan MacNeil (Linda Blair), a teenage girl who had been possessed by a demon in the first film. She is now undergoing psychiatric treatment and is being monitored by Father Philip Lamont (Richard Burton), who is investigating the death of Father Merrin (Max von Sydow), the priest who had performed the exorcism on Regan in the first film.

As Lamont delves deeper into the case, he discovers that the demon that possessed Regan is still alive and well, and is now seeking revenge on those who were involved in the exorcism. Lamont enlists the help of a scientist named Dr. Gene Tuskin (Louise Fletcher) in an attempt to communicate with the demon and learn more about its motives.

“Exorcist II: The Heretic” received largely negative reviews upon its release and was a box office disappointment, failing to recapture the success of the first film. However, it has gained a cult following over the years and is now considered by some to be a camp classic.