The film tells the story of a bunch of hippies (remember, this was made in the early 70s) who spend a night on a lonely island. All of them are killed except for one girl. Logical thinking leads the police to conclude she must be the murderer then, and they lock her up at the lunatic asylum. Relatives and local fishermen, however, believe there must be someone else – or something else – lurking on the island. They are courageous or stupid enough to start exploring the dark caves in the rocks… The whole set looks really cheap, but apart from that I liked the movie. It is exactly in the middle between old-fashioned 60s Hammer horror and 80s splatter movies, which means there are still traces of gothic atmosphere like the lighthouse in the fog, but already a few effective, vicious shock effects, too.