A famous scientist invents a humanoid robot (the titular "monster"), so a greedy rival scientist plans to steal it for use in his criminal plans. His henchmen often kidnap a trained gorilla (the titular "ape") from the zoo, to aid in the schemes.
Robert Lowery
George Macready
Ralph Morgan
Carole Mathews
Willie Best
Jack Ingram
Anthony Warde
Ted Mapes
Eddie Parker
Stanley Price
Charles King
Kenneth MacDonald
Bud Osborne
Ray Corrigan
John Elliott
Kit Guard