Camille has lost many things : her yellow pullover, the book she was currently reading, her grand ma... She soon finds herself working in the Lost property office. One day, she receives the visit of a little boy looking for his teddy bear, an old man looking for his memories, and Mary Poppins, who has aged a little and has a tendency to repeatedly lose her umbrellas. In this office, where most people are more lost than objects, Camille hopes to find a needle in a haystack.