Liverpool, 1940: Thirteen-year-old Joan's home is under constant threat from the Nazis' terrifying nightly air raids. Everyone is on edge, faced with strict food rationing, curfews, and blackouts. It's not an easy time to be a teenager. Joan's one solace is going to the movies with her best friend, the unflappable Doreen, but when the bombings intensify, even that becomes too dangerous. There's also the matter of a strange man who Joan sees lurking near their home. Who is he, and why does he think Joan can help him? Even more unsettling, as the Blitz worsens, Joan and her friends make a discovery down by the old mill that will tear the whole community apart. In the hardship of war, everything seems to be rationed except true friendship.