Murder on the Orient Express
After catching the Taurus Express from Aleppo in Syria and traveling to Istanbul, private detective Hercule Poirot arrives at the Tokatlian Hotel. Once there, he receives a telegram prompting him to return to London. He instructs the concierge to book a first-class compartment on the Simplon-Orient Express leaving that night. However, the train is fully booked, and Poirot only gets a second-class berth after the intervention of his friend M. Bouc, a fellow Belgian who is a director of the train line Compagnie Internationale des Wagons-Lits and is also boarding the train. After boarding, Poirot is approached by Samuel Ratchett, a malevolent, elderly American. Ratchett believes his life is being threatened and attempts to hire Poirot but, due to his distaste, Poirot refuses.
On the second night of the journey, as he is only travelling to Italy, M. Bouc gives up his first class-compartment to Poirot, who is going to Calais. This gives Poirot the compartment next to Ratchett. The train is stopped by a snowdrift near Vinkovci (spelled Vincovci in the book). Several events disturb Poirot's sleep, including a cry emanating from Ratchett's compartment. The next morning, M. Bouc informs him that Ratchett has been murdered and asks Poirot to investigate.
After Poirot and Dr. Constantine examine Ratchett's compartment, Poirot finds a note with the words '-member little Daisy Armstrong' on it, which causes him to ascertain Ratchett's real identity. A few years before, three-year-old heiress Daisy Armstrong was kidnapped by a man named Lanfranco Cassetti, who collected a ransom and killed the child. Cassetti was caught but fled the country after he was acquitted on a technicality. Poirot concludes that Ratchett was Cassetti.
Poirot discovers that everyone in the coach had a connection to the Armstrong family and a motive to kill Cassetti. He proposes two possible solutions. The first solution is that a stranger boarded the train and murdered Cassetti. The second one is that all of the passengers conspired to murder Cassetti. Mrs. Hubbard, revealed to be the famous actress Linda Arden, Daisy Armstrong's grandmother, confesses that the second solution is the correct one. M. Bouc and Dr. Constantine choose to present the first theory to the Yugoslavian police.