But five-thirty came and went in silence. Then five forty-five, and six o’clock. Just when Rudi began to think someone had squealed on them, the siren wailed.

They heard boots hitting the earth and the shouts of an Unterscharfuhrer and the clicking of a hound’s nails on the wood above them and then eventually silence. They spent three days without food or drink, stiff and motionless in the cavity. Bombs from an air raid pounded nearby. Then, on the third day, a few hours after they heard the SS guards call off the search, Rudi and Fred decided to emerge. The planks above them, however, wouldn’t budge.

It took all their strength to lift the wood, but finally it gave, and the night opened above them. They had roughly eighty miles of Nazi-occupied Poland ahead of them.