A mid-air murder aboard a commercial flight forces Hercule Poirot to identify a killer among a confined group of twelve passengers. As the plane travels from Paris to London, an elderly woman is found dead, leaving the detective to navigate a locked-room scenario where the weapon is as elusive as the culprit. Poirot must rely on his meticulous observation of human behavior and psychological patterns to dismantle the alibis of the suspects. The narrative follows a classic whodunit structure, utilizing Poirot's methodical perspective to sift through the conflicting testimonies of the passengers.

This novel is widely regarded as a quintessential example of the golden age detective story, praised for its clever use of a restricted setting. Readers often highlight the ingenuity of the murder method, which remains a frequent point of discussion in analyses of Christie's technical skill. The characterization of Poirot is frequently noted for its consistency and sharp wit, providing a stable anchor for the complex plot. The work is generally viewed as a successful exercise in logical puzzle-solving that maintains tension despite the limited physical space of the airplane cabin.