To suck a little more of the green stuff out of the "Exorcist" trademark, producers recruited the author of the original best-selling novel to write and direct this third and hopefully final entry in the franchise. But for all his writing talents, Blatty is a poor filmmaker.
Serial murders in New York appear to be linked to the possession of Linda Blair's character in the first film. It's up to homicide detective Scott to figure out the connection—and find out why some who looks like the priest who committed suicide in Part 1 (Miller) is alive in a mental ward and apparently possessed by demons.
"Exorcist III" feels awkwardly paced. The story is confusing. Only one of the scares delivers any real shock value. The picture is helped by the appearance of Brad Dourif as the Gemini Killer. But it isn't enough to save this mess. Blatty wrote an interesting movie, but needed a real director to deliver the vision. Hardcore fans of the first films may want to see this, since it is by the same writer. Others should pass.