Based on true events from the summer of 1939, the film follows teacher Thomas Miller (Eddie Izzard) who has taken a role teaching English to the daughters of high ranking Nazis at a finishing school on the south coast of England. Under the watchful eye of headmistress Miss Rocholl (Judi Dench) the girls learn deportment, Shakespeare, fitness and how to be a faithful member of the Hitler's League of German Girls, whilst practicing their English. When the body of a former teacher is discovered it triggers a sequence of deadly events and leaves Thomas running from the police.

Starring Eddie Izzard, Judi Dench, Jim Broadbent