Death in the Clouds
Agatha Christie
 Frustrated with the evident artificiality of the blowpipe, an item that could hardly have been used without being seen by another passenger, Poirot suggests that the means of delivering the dart may have been something else. Is it the flute of one passenger, or perhaps one of the ancient tubes carried by one of the two French archaeologists on board? Or maybe Lady Horbury's long cigarette holder? Poirot's focus is upon a wasp that has been seen in the compartment and which provided evidence for the original theory of the cause of death. Without explaining himself, he asks for a detailed list of the items in the possession of the passengers, and finds an incriminating clue: Norman Gale, a dentist who has seemingly never been in the area of the plane where the victim was killed, and has no apparent motive for committing the murder, had an empty matchbox and a lighter. He appears to be the killer, but how can he have committed the murder, when he was apparently in conversation with Jane Grey (the novel's effective heroine) throughout the flight? And why would he have committed the crime? And why were there two coffee spoons in the victim's saucer? Madame Giselle is suspected of using blackmail to ensure that her clients pay up, so any one of the passengers could either have owed her money or feared exposure. Equally, Madame Giselle had an estranged daughter who inherits her considerable estate: could one of the female passengers be this heiress? Much of the novel focuses on the pursuit of this line of enquiry, with the passengers coming under suspicion in turn. Special attention is given to Mr. Clancy, a detective novelist who enables Christie to include the same sort of parodies of her craft achieved in other novels through the character of Ariadne Oliver. The only other suspect who proves of material significance is, however, the Countess of Horbury, whose maid has been called into the compartment during the flight where she would have had the perfect opportunity to commit the crime. When this maid is revealed to be none other than the victim's heir, Anne Morisot, it seems that she must be the murderess. But the maid was only on the flight by accident, having been asked to be there at the last moment. Moreover, the death of Anne Morisot from poison on the boat-train to Boulogne leaves no clear suspect. Poirot reveals in the dénouement that Horbury is none other than Anne's new husband, and that his plans - almost certainly including the eventual murder of Anne herself - had been laid well in advance. He brought his dentist's jacket on board and - in the apparently innocuous moments that he had gone to the toilet - changed into this jacket in order to pose as a steward. Under the pretense of delivering a coffee spoon to Miss Giselle he had walked up the aisle and stabbed her with the poisoned thorn. As Poirot puts it: "No one notices a steward particularly." Gale's intention had been to frame the Countess, and the blowpipe that was found behind Poirot's seat would have been found behind hers had they not switched seats at the last moment. Not content with solving the mystery, Poirot also invites Mr. Clancy to the dénouement where he gleefully allows the novelist to see how a real-life Detective solves a case, to both men's great enjoyment. Finally, in a single stroke Poirot makes a romantic match by pairing off Jane Grey with the younger of the archaeologists.