Ewen has a secret that he has kept from everyone and nobody knows about it. He goes out at night in the streets of Paris, which would worry any parent of a young boy. But Ewen doesn't live at home with his mother and father. He lives in a hospital because he has cancer. And his cancer doesn't keep him from going out on adventures. When a boy named Benjamin is hospitalized for the same reason in the same hospital, Ewen and Benjamin become friends...