Stuart Rosenbergs 1979 film launched a long-running franchise, so it mustve done something right, but in later years the film had its thunder stolen by Paranormal Activity and Insidious, which handled similar themes with more economy and, crucially, more credibility. Horror only works if you believe the set-up, and its hard to buy into a movie where ghosts make $1500 in cash disappear or Father Rod Steiger gets attacked by flies. Even at its worst, the Paranormal Activity franchise never stooped so low as to launch an insect attack on a Priest. For a film based on a true story its remarkable how many scenes youve seen in other haunted house movies: the babysitter gets locked in a cupboard, a child has an imaginary playmate, the house causes a nun to be physically ill etc. If this actually happened, shouldnt the filmmakers be suing for plagiarism?