Calificación
Reparto

Roy Barcroft
The Purple Monster

James Craven
Dr. Cygnus Layton

Dennis Moore
Craig Foster

Linda Stirling
Sheila Layton

Bud Geary
Hodge Garrett

Joe Whitehead
Stewart

Fred Howard
Prof. Crandal

Rosemonde James
Helen

Mary Moore
Marcia

John Davidson
Emperor of Mars

Wheaton Chambers
Prof. Benjamin