leven-year-old Marianne Cadogan lives a lonely life with her stern, often absent father in a big house by the sea. When, one day, a stranger rescues Marianne from the rising tide, she believes she's found a friend at last. Then Marianne and her rescuer, Ryan O'Donnell, vanish. While Patrick Cadogan convinces the police his daughter has been kidnapped, Marianne and Ryan race to Germany in search of her missing mother and a secret that Marianne must never, never be allowed to discover.