Its 1940 & war is underway. In Sheffield England a brother & sister set out to solve a mystery brazenly believing that the air-raid signals are only false alarms. In Dachau Germany two boys come up with a bold plan to bring an end to the war & help a Polish prisoner escape. But when the bombs falling on Sheffield become a reality & the German boys plan hurls them unwittingly into the midst of the action the childrens adventures swiftly become a terrifying fight to survive.