Death in the Clouds (1935) is a novel by Agatha Christie.

Plot

Hercule Poirot, the idiosyncratic yet brilliant detective, is one of eleven passengers in the rear car of the noon flight from Paris to Croydon. Some time before landing, one of the passengers, Madame Giselle — moneylender to the downwardly-mobile upper classes — is found dead. Initially, a reaction to a wasp sting is postulated, but then Poirot's gimlet eye spies the true cause of death: a poison-tipped dart, fired apparently from a blowpipe. Clearly murder is afoot.

One of the passengers or stewards must be the perpetrator, but which one is it? The Countess of Horbury, coke-addled, debt-ridden gamblaholic? Armand Dupont, eminent archaeologist and, as a shifty foreigner, as likely to be the culprit as not? Or even our beloved Poirot? After all, he's foreign too.

Comment

Much the same as most of the celebrated Dame's murder mysteries, complete with the usual 1930s English upper-middle class attitudes toward those who aren't upper-middle class and English.