The Exorcist was made into the movie "The Exorcist III" in 1990. Like "The Exorcist", it involves demonic possession. The book was the focus of a court case over its exclusion from "The New York Times" Best Seller list. Blatty based aspects of the Gemini Killer on the real-life Zodiac Killer, who, in a January 1974 letter to the "San Francisco Chronicle", had praised the original "Exorcist" film as "the best satirical comedy that I have ever seen". The Exorcist is a 1973 American supernatural horror film directed by William Friedkin, adapted by William Peter Blatty from his 1971 novel of the
The Exorcist into the legitimacy of Merrin's exorcism of Regan in the first film. In flashback sequences, we see Regan giving Merrin his fatal heart attack, as well as scenes from the exorcism of a young boy named Kokumo in Africa many years earlier. "The Exorcist III" appeared in 1990, written and directed by Blatty himself from his own 1983 novel "Legion". Completely ignoring the events of "Exorcist II", this book and film presented a continuation of Karras' story. Following the precedent set in "The Ninth Configuration," Blatty turned a supporting character from the first film – in this case, Kinderman —