Autumn 1929 - a young girl is kidnapped from a beach. Five agonising days go by before she is discovered safe and well in a nearby village. The child remembers nothing of these events and at home, nobody ever speaks of them again. Decades later, Laura Cumming delves into the mystery surrounding her mother's disappearance. Examining everything from old family photos to letters, tickets and recipes, she uncovers a series of secrets and lies perpetuated not just by her family but by the whole community and in doing so unlocks a mystery almost a century old.