Murder on the Orient Express opens with Hercule Poirot, an international detective, arriving in Stamboul. However, Poirot receives a message causing him to travel back to England. When he arrives on the train, he is amazed at how crowded and busy it is, during the usual slow time of year. Samuel Ratchett, an American passenger, believes he is in danger. After learning Poirot is a detective, Mr. Ratchett attempts to hire him. Poirot rejects the business offer, claiming he doesn’t trust him. As the train continues on its’ journey through the night, it suddenly is stopped due to a snow drift. Poirot wakes, hearing someone speaking French in Ratchett’s neighboring compartment. Looking out into the hall, Poirot sees a figure wearing a scarlet kimono leave. The passengers wake up the next morning to find Mr. Ratchett murdered. M. Bouc reveals Mr. Ratchett was stabbed twelve times, resulting in his death. Poirot is assigned to the case with the help of M. Bouc and Dr. Constantine. After investigating the crime scene, Poirot finds a slip of paper saying “-member Daisy Armstrong”. The partially burned paper reveals that Mr. Ratchett was actually Cassetti, the kidnapper and murderer of baby Daisy Armstrong in America. Cassetti was able to escape his death sentence, then disguised himself into Mr. Ratchett. Poirot also finds a smoking pipe, handkerchief, and a piece of the scarlet kimono in Ratchett’s compartment. After questioning the train passengers, Poirot finds that every single passenger has an alibi- whether or not they had motives or evidence against them. Multiple passengers also admit to seeing someone on the train in a scarlet kimono.As Poirot continues to ponder a solution to the crime, he comes to the realization that many of the passengers had lied and many of them had connections to the Armstrong family. Countess Andrenyi had lied about her Christian name and was Daisy’s aunt. Mary Debenham was Daisy’s governess, Princess Natalia Dragomiroff was Daisy’s godmother, Miss Greta Ohlsson was Daisy’s nurse, and Schmidt was the Armstrong cook. The list goes on to list twelve people on the train that had relation to the Armstrongs, including Cassetti/Mr. Ratchett’s secretary McQueen. The only passenger who told the truth about their relation to the Armstrongs in their original testimony was Colonel Arbuthnot, who was close friends with Colonel Armstrong.Poirot in the end comes to two different solutions. The first solution suggests that the killer was able to escape the train right before it got stuck in the snow. However, the second solution is much more complex. Poirot suggests that the trade ride was planned ahead of time and the passengers worked together to kill Cassetti. The Colonel admits it was his plan, claiming Cassetti deserved the punishment he avoided. Since Cassetti was able to escape the death sentence, the Colonel deemed that if there were twelve killers, the same number as the amount of jurors, they themselves could sentence him to death. The twelve passengers/killers admit that the loss of Daisy Armstrong negatively impacted their lives and they thought she deserved justice. Their plan was for each passenger to have an alibi, so the killer would have been suspected to to leave the train in the middle of the night. The original plan was foiled thanks to the snow drift. After the murder plot was revealed, Poirot decided to keep the matters a lot less complex and tell the police the first solution.