Stars Boris Karloff, Evelyn Keyes and Edward Van Sloan. Karloff is a scientist experimenting with a "fountain of youth" drug. He injects himself and watches the years drop away. His friends won't go along with being guinea pigs too, and the drug takes its toll on Karloff. He progresses into a maniac. Edward Van Sloan (FRANKENSTEIN and DRACULA) appears as a prison doctor who works with Boris....until.....