Dr. Truman Harwell
Eleanore Leavenworth
Gloria Leavenworth
Phoebe Leavenworth
O'Malley
Hudson
Detective Bob Grice
Silas Leavenworth
Henry Clavering
Inspector Holmes
Miss Owens
Duke
The Bulldog Woman
The Pekingese Woman
Sarah - a servant
Leavenworth-Clavering Bookkeeper
Chemical Analysist
Miss Hill
Fingerprint Expert
The Cat Woman