Bela Lugosi

Dr. Melcher/ Monsieur Colomb

Clayton Moore

FBI Agent Richard ‘Dick’ Martin

Joan Barclay

Alice Saunders

George Pembroke

Dr. William Saunders

Robert Frazer

Amos Hanlin

Robert Fiske

Phillip Wallace

Irving Mitchell

John Van Dyke

Edward Peil Sr.

Ryder

Kenneth Harlan

FBI Chief Colton

Max Hoffman Jr.

Kearney

Joseph Eggenton

Stevens

I. Stanford Jolley

The Dragon

Frank Melton

FBI Agent

Sam Katzman

Producer

Johnny Lange

Music

Arthur Reed

Director of Photography

Jack Dietz

Production Manager

Carl Pierson

Editor

William Nigh

Director

Glen Glenn

Sound Engineer

Dave Milton

Art Direction

Lew Porter

Music

Heinz Roemheld

Music

Jack Dietz

Producer

Gerald Schnitzer

Assistant Director

Arthur Hammond

Assistant Director

Harvey Gates

Original Story

Robert Kehoe

Story

Harvey Gates

Screenplay