From seat No. 9, Hercule Poirot was ideally placed to observe his fellow air passengers. Over to his right sat a pretty young woman, clearly infatuated with the man opposite, ahead, in seat No. 13, sat a countess with a poorly concealed cocaine habit, across the gangway in seat No. 8, a detective writer was being troubled by an aggressive wasp. What Poirot did not yet realize was that behind him, in seat No. 2, sat the slumped, lifeless body of a woman.