Reverend Stephen Babbington attends a party, has a cocktail, and dies. With no trace of poison and no motive for murder, the death is ascribed to natural causes. At another party, with the same guests, another person dies in exactly the same manner. Hercule Poirot, present at the first gathering, takes on the baffling case. He stages his own party, gathering all the suspects together. Is he setting himself up to find the truth, or setting the stage for another murder?