Sabotage (1936)

In 1930s London, Karl Verloc, a mild-mannered cinema owner, leads a secret life as part of a terrorist plot. While his wife, Sylvia, and her teenage brother, Stevie, are unaware of his double life, Scotland Yard suspects him. They assign undercover detective Ted Spencer to a greengrocer's shop next door to monitor Verloc's activities. Under pressure and surveillance, tensions mount, secrets unravel, and lives are forever altered.