When the movie starts, the horror becomes real. The TV ads promised a festival of cheap and bloody fright films, all of them thinly disguised knockoffs of well-known movies with much better pedigrees. One film features a family of chainsaw maniacs, another a zombie uprising. In yet another, a cult of vampires lives in a creepy old mansion. The whole thing is hosted by the mysterious Dr. Ominous. Entranced by the ads, a small group of...