Paul Beaumont is a success with his paintings of human terror. Feeling exhausted he goes to work on one final masterpiece. He scares a model to death and paints the ultimate terror. The ghost of the woman, however, urges him on to work until he collapses.; The couple of John and Alice gets lost in the countryside. They come to the home of Senor Gato who lives in the company of cats. Or rather cat-beings able to take on human form as well. Alice is transformed into a cat and John accidentally kills her.; A young carpenter comes into possession of Jack the Ripper’s knife and is haunted by visions of murder. He goes on a killing spree, unable to stop or get rid of the murderous weapon.; Elderly Dr. Gordell drinks a potion which transforms him into strong, primeval cave-man. As such he roams around and murders innocent passers-by. Gordell’s daughter and his assistant Roger can track him down and get him engaged in a death-match with a circus gorilla.