Lionel Atwill stars as Jerome Breen, a stock broker and noted philanthropist who has committed a series of cold-blooded murders. Witnesses near the scene of the crimes recount that Breen had spoken to them moments after the murders were committed, however, Breen has an airtight alibi - he is a deaf mute. As the investigation unfolds, Inspector Riley (Robert Ellis) discovers a clue that will solve the mystery, but will he be able to bring the wealthy socialite to justice? Atwill is beloved by fans for his roles in <i>Mystery of the Wax Museum</i>, <i>Dr. X</i>, <i>The Vampire Bat</i> and many Universal horror films. He also is noted for his portrayal of Professor Moriarty in <i>Sherlock Holmes And The Secret Weapon</i>.