The Stooges are private detectives that are hired to track down a kidnapped girl name Mary Bopper (Norma Randall), daughter of George B. Bopper. They decide to trace Bopper back to where she was last seen, which leads them to mad scientist Dr. Jeckyl (Philip Van Zandt) and his assistant, Mr. Hyde (Tom Kennedy). There is also a gorilla kept imprisoned in the house for experimental purposes. The Stooges arrive to rescue the kidnapped girl disguised as door-to door pie salesmen.