It is June 1940, and Britain faces the threat of imminent invasion. As the Battle of Britain looms, the villagers of Great Paxford live under a cloud of fear and suspicion. Pat strikes up a friendship with a Czech soldier stationed nearby, but her joy at independence from Bob is short lived. Meanwhile, Laura is forced to face the consequences of her affair with Richard Bowers, and Spencer and Claire's relationship takes an unexpected turn. Sarah receives shocking news about Adam.