When John Darwin walks into a shop in London, it causes an instant stir. After all, John Darwin has been dead for five years. He claims to have amnesia, but everyone - from the police and the media to his insurance company - suspects he is lying. No one can prove a thing, until a young woman at home with her baby thinks of something everyone else has missed.   For the show notes, see timharford.comSee omnystudio.com/listener for privacy information.