 Following the death of his sister, who was co-director with him of the Cowan Research Center in Pasadena, Dr. Frederick Munson was ousted and replaced by his widowed brother-in-law, Dr. Edmund Redding. Through Redding s son, Timmy, Munson has been able to learn of a secret project at the institute involving the use of hypnosis to regress subjects to past lives, which information Munson passes along to a friend, Dr. John Janney. To a newspaper editor-friend, Munson relates what happened next: through the hypnotic regression, Redding established that Ann Taylor was a reincarnated Aztec woman and, via her recovered memories, was able to find hidden chambers in the Great Pyramid of Yucatan, which store a treasure of the ancient Aztecs. However, the treasure was guarded by a living mummy, which killed Redding but was captured and brought back to Pasadena by Redding s assistants. As Munson conspired to regain control of the Cowan Institute, Janney plotted to steal the mummy and learn its secrets. A hired thief locates the mummy, but it escapes him, and makes for the home of Ann Taylor...