George Zucco

as Egyptian Ambassador (uncredited)

as Dubocage

as Judge

as Dr. Fortescue

as The Viceroy

as Palanth, the High Priest

as Doc Robbin

as Marquis De Carvajal

as Father Donnard

as H.R. Barrett

as Craxton

as Dr. Josef Van Ee

as Prof. Andrew Forbes

as Dr. Pavel Storasky

as Detective Geddes

as Bey of Aribajan

as Jelke

as Leo Grainger

as Prof. Bruno Lampini

as Ape Man

as Andoheb, High Priest of Arkan

as Nicholas

as Dr. Alfred Morris

as Mr. Crepitude

as Amos Bradford

as Lloyd Clayton / Elwyn Clayton

as Heinrich Hinckel aka Richard Stanley

as Lord Denby

as Andoheb

as Dr. Robert Renault

as Lorenzo Cameron

as Dr. Hugo Streger

as Defense Attorney

as Dr. Jeris

as Dr. Parry

as Prison Governor

as Professor Andoheb

as Lawyer Crosby

as Professor Moriarty

as Procurator

as Dr. Cardigan

as Rolf Alferson

as Prime Minister

as Otto Brockler

as James 'Jim' Hampstead

as Count Armalia

as Woodley

as Dr. Bierd

as Dr. Kammer

as The Colonel's Butler