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
Ken Morgan
George Macready
Prof. Ernst
Ralph Morgan
Prof. Franklin Arnold
Carole Mathews
Babs Arnold
Willie Best
Flash
Jack Ingram
Dick Nordik
Anthony Warde
Joe Flint
Ted Mapes
Joe Butler
