Nazi Agent

Humble stamp dealer Otto Becker (Conrad Veidt) has little to do with international politics, so when he receives a surprise visit from his estranged twin brother and Nazi spy, Baron Hugo von Detner (Conrad Veidt), his world is thrown into turmoil. Threatening Becker with deportation, Hugo forces him to use his shop as a front for espionage. But when Becker's friend Professor Sterling (Ivan Simpson) turns up dead, Becker accidentally shoots his brother and assumes his identity.