Man from the Unknown (1939)

While in Bohemia, an American industrialist named Craigs goes missing. In Prague, the police have arrested a man without identification, who bears a striking resemblance to Craigs. The doctor, the secretary, and the hotel staff all claim that he is the industrialist. The man denies this claim. When he learns how harsh and despotic the man he is believed to be is, he agrees to go to London and adopts his new identity.