David is a twelve-year-old boy who has spent his entire living memory in a bleak Eastern European concentration camp. Having known only deprivation and cruelty, he relies on a strict moral code and fierce independence to survive. He travels across Europe equipped with a compass and a piece of soap, slowly learning to trust others and appreciate the physical world. He is highly intelligent and speaks multiple languages fluently.

Johannes is an older prisoner in the concentration camp who served as David's primary caretaker. Though he died of a heart attack three years before David's escape, his teachings about personal responsibility and courage continue to guide the boy. His voice remains a psychological anchor for David during moments of intense fear.

The Man is an unnamed guard at the concentration camp who holds a position of authority over the prisoners. He inexplicably sets up an escape route for David, providing a compass, bread, and directions to Denmark. Despite his life-saving actions, he remains a detested figure in David's mind due to his role in the camp.

Maria is a young girl living in a luxurious home in Northern Italy with her parents and four brothers. She accepts David without judgment despite his unusual adult mannerisms. Her friendship brings David his first moments of genuine happiness since leaving the camp.

King is a farm dog owned by a harsh family in Switzerland. He recognizes David's inherent goodness and offers him much-needed loyalty. The dog willingly chooses to accompany David after he breaks out of the stable, offering silent support during dangerous crossings.

Carlo is Maria's oldest brother, a hot-tempered boy who initially views David as a trespassing thief. He physically attacks David before understanding the boy's true nature. His actions remind David of the cruelty he experienced in the camp, though Carlo later attempts to make amends.

Giovanni is the wealthy patriarch of the Italian family that takes David in. He offers David shelter and medical care to express his gratitude. While he tries to be accommodating, he remains puzzled by his young guest's adult mannerisms.

Elsa is Maria's mother. She is highly protective of her children and grows increasingly concerned by David's unlikely stories. Her private doubts about David's background ultimately prompt his decision to leave their home.

Andrea is one of Maria's younger brothers. He owns a globe that fascinates David and helps the boy understand the geography of Europe. His casual attitude toward playing games about prisoners deeply disturbs David.

Sophie is a middle-aged Danish woman living in Switzerland who works as an artist. She invites David into her home and shares a meal with him. Her collection of photographs provides David with a vital clue about his destination in Denmark.

Edith is a woman living in Denmark whose husband and child were reported killed due to political turmoil. She escaped her dangerous home country and relocated to Copenhagen. Her photograph in a Swiss artist's album catches David's attention and gives him a specific address to seek out at the end of his journey.

The Farmer is a harsh agricultural worker who traps David during a heavy snowstorm. He leverages the threat of police discovery to treat the boy as unpaid labor. He locks David in a stable with the animals at night to prevent him from running away.

Angelo is a kindhearted Italian truck driver who picks David up on the side of the road. He drives the boy to Perugia, cheerfully sharing details about his own life and future plans, which helps soften David's fear of strangers.

The Italian Sailor is a crew member on the boat David stows away on in Salonica. Instead of turning the young boy in, he secretly brings him food and provides a lifebelt, gently lowering him into the water off the coast of Salerno so he can reach land safely.