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

William Nigh