Directed by Lambert Hillyer
Produced by Edmund Grainger
Executive Producer : Fred S. Meyer
Written by John Colton
Story : Howard Higgin and Douglas Hodges
Cinematography by George Robinson
Film Editing by Bernard W. Burton
Score and Adaptation by Franz Waxman
Art Direction by Albert S. D'Agostino
Makeup : Otto Lederer, Jack P. Pierce
Special Effects by John P. Fulton, Raymond Lindsay
Cast
Boris Karloff (Dr. Janos Rukh)
Bela Lugosi (Dr. Felix Benet)
Frances Drake (Diana Rukh)
Frank Lawton (Ronald Drake)
Violet Kemble Cooper (Mother Rukh)
Walter Kingsford (Sir Francis Stevens)
Beulah Bondi (Lady Arabella Stevens)
Frank Reicher (Prof. Michaeljohn)
Paul Weigel (Monsieur Noyer)
Georges Renavent (Chief of the Surete)
Ernie Adams
May Beatty (Mme. LeGrand)
Helen Brown (The Blind Girl's Mother)
Ann Marie Conte (The Blind Girl)
Dudley Dickerson (Native who first sees Rukh glow)
Winter Hall (The Minister)
Daniel L. Haynes (Rukh's Head Bearer)
Etta McDaniel (Diana's Safari Attendant)
Walter Miller (The Derelict)
Hans Schumm (The Clinic Valet)
Ynez Seabury (Celeste, a maid)
Lawrence Stewart (The Runner-boy)
Adele St. Mauer (Mme. Noyer)
Ray Turner (Bearer with Geiger Counter)
Lucio Villegas (Pierre, the butler)
Nydia Westman (Briggs, a maid)