Jewish refugee Ella Rosenthal has finally found a safe haven. It has been three years since she and her little sister, Hanni, left their parents to flee Nazi Germany, and they have been pursued and adrift in the chaos of war ever since. Now, they shelter among one hundred other young refugees in a derelict castle in Southern France overseen by the Swiss Red Cross. However, when Germany invades southern France, Swiss volunteers Rosli and Anne-Marie realise that the only way to protect the eldest of their charges is to smuggle them through vast Nazi-occupied territory to the distant border.