Diễn viên
Boris Karloff
James Lee Wong
Evelyn Brent
Olga Petroff / Countess Dubois / Sophie Dome
Lynton Brent
Tommy
Wheaton Chambers
Chemistry Lab Director (uncredited)
Clancy Cooper
Warehouse Man (uncredited)
Lester Dorr
Coroner (uncredited)
John St. Polis
Carl Roemer
John Hamilton
Simon Dayton
Ed Cassidy
Ambulance Doctor (uncredited)
Herbert Evans
Wilk's Butler (uncredited)
Lucien Prival
Anton Mohl
William Gould
Theodore Meisle
Wilbur Mack
Russell
Grant Withers
Police Capt. Sam Street
Maxine Jennings
Myra Ross
George Lloyd
Devlin
Hooper Atchley
Christian Wilk
Lee Tung Foo
Tchin