Yellow Canary.

In 1940 Sally Maitland is forced to leave England, ostracised as a Nazi sympathiser by everyone including her well-to-do family. On the ship to Halifax, Canada, she is courted by Polish aristocrat Jan Orloch and by awkward British navel intelligence officer Jimmy Garrick. She shows herself somewhat more amenable to Orloch's advances, and agrees to meet his mother in Halifax. Once there however, it becomes clear no-one is really who they say they are.