Poirot has always hated visiting the dentist, but this time his check-up is painless and soon over. As he leaves Mr Morley's surgery, he observes a woman wearing patent leather shoes with large buckles. She catches one of the buckles on the taxi door and wrenches it off, and as Poirot hands it back, he is reminded of the children's rhyme 'One, two...
The first message sent to Tom Thorne's phone was just a picture - the blurred image of a man's face, but Thorne had seen enough dead bodies to know that the man was no longer alive. But who was he? Who sent the photograph? And why? While the technical experts attempt to trace the sender, Thorne searches the bulletins for a reported death that matches the photograph. Then another picture arrives.