Sabotage (1936)
Mr. Verloc (Oscar Hamolka) is part of a gang of foreign saboteurs operating out of London. He manages a small cinema with his wife and her teenage brother as a cover, but they know nothing of his secret. Scotland Yard assign an undercover detective, Det. Sgt. Ted Spencer (John Loder) to work at the shop next to the cinema in order to observe the gang.