The previous movie with Russell as an exorcist didn't seem to go down well with the Pope, so the project was handed over to different producers who thought he’d be more successful playing a debauched actor ("Anthony") cast in the role of a priest performing exorcisms. However, what "Anthony" doesn’t realize is that the film set itself harbors an evil spirit – who seems to have gotten rid of the previous director (or possibly left willingly) – and now wants to create more trouble. Fortunately, director "Peter" (Adam Goldberg) brought in a genuine priest (David Hyde Pierce) to ensure the religious elements were accurate while "Anthony" and his co-star "Joe" (Sam Worthington) struggle with increasingly realistic dreams, numerous exploding light bulbs, and some rather brief moments of demonic dancing. There’s simply nothing good about this film. It lacks originality and humor. The performances are stiff, and it feels as though the script was based on a children's book about priests and horror, mistakenly believed to be suitable for a movie. Neither of the well-known actors involved benefits from their involvement, and the film concludes, anticlimactically, at what feels like the perfect time. A release date around October or Halloween might have helped, but as it stands, this is just a disappointing example of someone’s fall from grace.

Source on TMDB