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

Ronald Davidson

Producer

Marlin Skiles

Original Music Composer

Albert DeMond

Screenplay

Barney A. Sarecky

Screenplay

Milton Rosen

Original Music Composer

Fred C. Brannon

Director

Lynn Perkins

Screenplay

Spencer Gordon Bennet

Director

Basil Dickey

Screenplay

Royal K. Cole

Screenplay

Bud Thackery

Director of Photography

Joseph F. Poland

Screenplay

Charles Maxwell

Music

Ed Borschell

Sound