It's 1950: 15-year old Henry Dodge lives with his mother Maureen and her new husband Bill. Encouraged by his embittered and meddling paternal grandmother, Henry refuses to accept Bill and wishes to keep alive the memory of his father Joey, a decorated Dunkirk hero killed by a deserter during an air raid. After new class-mate Grace and kindly school teacher Mrs Beaumont have persuaded Henry to forgive Paul Jeffries (the deserter's son), Joey appears claiming to have lost his memory and anxious to get his family back. But Grace is right to be suspicious of him, and the stories told by Henry's mother support her...