The Mad Ghoul

Medical student Ted Allison is engaged to singer Isabel Lewis. Isabel is having a difficult time telling Ted that she is no longer in love with him, having instead fallen in love with her accompanist and Ted's friend, Eric Iverson. While Isabel and Eric are scheduled to head off on a summer concert tour, Ted is hired by his friend and well-respected college professor, Dr. Alfred Morris, to assist in conducting the latest phase of his research. That research is in the activities of an ancient tribe which developed an odorless and colorless poisonous gas that turned those who breathe it into the living dead - what Ted does not know were controllable zombies - who were revived to normal human state by the transplantation of a heart from a recently deceased or alive person. Ted learns that Dr. Morris has already recreated the gas and tested it out on a lab monkey named Jocko. They are able to successfully revive Jocko by a heart transplant. Ted is however unaware that Dr. Morris hired him solely to be his first human subject as he wants Ted out of the way since he himself loves Isabel. Dr. Morris' test on Ted is a success, having turned him into a zombie, made Ted rob a grave of a recently deceased person to cut out his heart, and transplanted that heart into Ted to revive him. After the process, Ted was unaware of what happened to him, only having vague dreams - nightmares - of such incidents. But Dr. Morris soon learns from what happens to Jocko that the heart transplant only has a temporary effect, meaning that Dr. Morris will need more human hearts to keep Ted alive. As Isabel often uses her friend Dr. Morris as a confidante, he learns about the personal role of Eric in her life, which adds the task of getting Ted to kill Eric followed by killing himself so that Dr. Morris can have Isabel all for himself. Through it all, the police and the print media are following the story of the grave robbings and murders, notably reporter Ken McClure, who notices that these incidents seem to be happening in the cities where Isabel is performing.