Death in the Clouds (1935) - starring the detective Hercule Poirot - written by Agatha Christie

Death in the clouds was a novel written by Agatha Christie, and released in 1935. Agatha Christie had based most of her stories on the ground, and this was probably her first story that was written about a murder on an aircraft. The book again stars her favorite detective, the proud Belgian detective with a head shaped like an egg, Hercule Poirot, with the book also featuring the constant police companion, Chief Inspector Japp.
Hercule Poirot is on a flight from Paris to Croydon Airport (an airport that used to service South London before it was replaced by the more modern airports of Heathrow and Gatwick). On this flight, one of the passengers, a moneylender by the name of Madame Giselle. There is initial speculation that she was killed by the bite of a wasp, but the sharp Poirot noticed that she was killed by a poison-tipped dart (the kind that are fired from a blowpipe). Which means that the death was not an accident, but was actually a murder, and hence Poirot is the chief person to do the murder investigation.



However, using a blowpipe on such a closed and intimate environment such as an aircraft would not be an easy task with the probability of being seen by somebody very high. More likely that the murder would be done through the use of another instrument such as a flute or some other pipe. And the murder victim, Madame Giselle, is not a very friendly person, since she was not above using blackmail to get her money back, so there would be a number of people who could have a possible motive if the pressure of the blackmail proved to be too heavy.
Suspicion can fall on many persons in the flight, turn by turn. For example, it turns out that some of the people are not who they were, or were linked to the victim in some way; and was there the question of passing of money also involved ? Was this a murder for financial gain ?