Boris Karloff

Prof. Morlant

Cedric Hardwicke

Broughton

Ernest Thesiger

Laing

Ralph Richardson

Nigel Hartley

Dorothy Hyson

Betty Harlon

Anthony Bushell

Ralph Morlant

Kathleen Harrison

Kaney

Harold Huth

Aga Ben Dragore

D.A. Clarke-Smith

Mahmoud

Jack Raine

Davis the Chauffeur (uncredited)

George Relph

Doctor (uncredited)