David is a twelve-year-old who has spent his entire life in a prison camp in eastern Europe. For reasons he does not understand, the head guard allows him to escape. He is told, without knowing why, to make his way to Denmark. He stows away on a ship to Italy, then travels north on foot, fearing everyone, eluding recapture, learning to survive in a world that seems entirely alien to him.
He has no family that he knows of, and knows nothing about himself or the world outside the camp. He is bright and reasoning, but has little useful experience, and thus misunderstands almost everything he sees. Other children he finds especially difficult, and the idea of imaginative play is completely beyond him. Yet some things, like brutality and evil, he understands all too well, and more clearly than many of the people he encounters.