Bela Lugosi as Dr. Charles Kessler

Polly Ann Young as Virginia Kessler

John McGuire as Ralph Dickson / Paul Dickson

Clarence Muse as Evans the Butler

George Pembroke as Lt. Williams

Betty Compson as Mrs. Kessler

Ernie Adams as Jules Mason, caretaker

Ottola Nesmith as Mrs. Mason

Terry Walker as Cecile Mannix, maid

Fred Kelsey as Detective Ryan

Jack Mulhall as Jim, a detective

Fred Aldrich as Guard at Ralph's Execution (uncredited)

Lloyd Ingraham as Psychiatrist (uncredited)

Robert Strange as Kirby--Coroner (uncredited)

Dorothy Vernon as Kessler's Cook (uncredited)

Robert F. Hill as Trial Judge (uncredited)