Murder on the Orient Express
(Agatha Christie)

Private detective, Hercule Poirot, is headed to Istanbul via train where he sees two people, Mary Debenham and Colonel Arbuthnot, acting as though they are strangers though Poirot is quite convinced they are not. Once Poirot checks in to his hotel he is summoned back to London and while waiting for a train he runs into his old friend, M. Bouc who offers him a ride on the Orient Express. That evening Poirot sees Ratchett, a man he considers evil, dining with Hector McQueen.

The next day, aboard the Orient Express, Ratchett tells Poirot that he has been getting death threats and asks Poirot to work for him and find out who has been sending the notes but Poirot refuses. The first night on the train Poirot notices some strange things happening, such as a noise from Ratchett’s room, a complaint from Mrs. Hubbard that a man is in her room, and the train stopping in a snow bank. In the morning, Poirot learns that Ratchett was murdered the night before, and he decides to take on the case.

After examining the body and taking into consideration some strange evidence, Poirot concludes that Ratchett is actually a man named Cassetti who kidnapped and murdered a child named Daisy Armstrong a few years back. After interviewing the other passengers and taking evidence into consideration Poirot discovers that the other passengers are not who they seem to be at all but instead were all a part of Daisy’s life and worked together to eliminate Ratchett.