A full-cast BBC Radio 4 dramatisation of an Agatha Christie story. On a flight from Le Bourget to Croydon, on which Hercule Poirot is an apprehensive passenger, a woman is found dead. A doctor on board is inclined to put it down to a wasp-sting, but Poirot suspects that a poisoned dart is the real cause...
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.