Murder on the Orient Express, or Murder in the Calais Coach, is an Agatha Christie detective fiction murder mystery first published in 1934. Hercule Poirot, the famous Belgian detective, is ready to return from his case in Syria when he is snowbound on the Orient Express. He is disturbed in his sleep by dead quiet and a passing figure in a red kimono, and when he awakes, the contemptible Ratchett is found having been stabbed 12 times to death. Poirot discovers he was actually a notorious American gangster, who had kidnapped and murdered a three-year-old heiress. The mystery begins to unravel as he discovers that the passengers have connections to the murdered man and the family of the child that man murdered.The book was made into a successful movie in 1974, a Made-for-TV Movie in 2001, and again in 2010 for Poirot.Warning: many unmarked spoilers are below as the plot is well known.
Adaptational Angst Upgrade: In the original novel and most adaptations, Hercule rather cavalierly lets the murderers go free, but in the 1974 film and especially the 2010 Poirot versions, he is deeply conflicted before finally making the choice.
Adult Fear: The first few minutes of the movie - and the motive for Ratchett's murder - are horrifying on their own, but they might be especially hard on parents.
All-Star Cast: The 1974 film version, which starred Albert Finney, Lauren Bacall, Sean Connery, Ingrid Bergman, Michael York, Vanessa Redgrave, Jacqueline Bisset, Anthony Perkins, Richard Widmark, Jean-Pierre Cassel and Sir John Gielgud, among others. Bonus point since they are not only international stars, but also all famous in their respective countries.
Asshole Victim: Ratchett's portrayed as a terrible man, so there isn't much sympathy when he is killed. We find out that he's so deserving of his fate that Poirot eventually lets his murderers go. This trope is exaggerated here.
Bittersweet Ending: While the murderers do get off scot-free, that's because even Poirot agrees that Ratchett's crime against the Armstrong family (who they all had connections to) had been paid back justly, with interest.
Eagleland: The portrayal of the U.S. makes it obvious that Christie didn't know very much about it. For example, Poirot says that it is "obvious" that the Hungarian ambassador stationed in Washington D.C. must have been acquainted with the Armstrongs, a prominent family from Chicago.
Caroline Hubbard embodies this whenever the opportunity presents itself. Then again, it's all an act.
The Americans are also referred to as subjects rather than citizens. Of course, it is Poirot and Bouc doing this, and they might not consider the distinction to be important.
Enclosed Space: Being snowed in was the only reason the crime wasn't a total success.
Everyone Is a Suspect: Deconstructed. Many murder mysteries set up the plot so that every character had a motive; but why would someone be in a situation where everyone in the vicinity has a motive to kill them? If the whole situation is the result of a conspiracy plotted by all the people with a motive to bring the victim among them.
The trope plays pretty much straight too. The only characters who are not suspects are Poirot himself, who was hearing some of the key events of the murder taking place and was asleep through others; and M. Bouc (Signor Bianchi in the 1974 film) and Dr. Constantine, who were incapable of being in the place of the murder at the time of the murder. In the 2010 adaptation, even the latter is one of the killers.
Evil Is Deathly Cold: In the 2010 adaptation, the train's generator fails soon after it runs into the snowdrift, so everything gets progressively colder and darker as Poirot comes closer to the truth.
Follow the Leader: Very influential, inspiring many "trapped on a transportation device with a murderer" stories.
Foreshadowing: The 1974 film has a couple of implications that Poirot recognized Mrs. Hubbard as Linda Arden from the very beginning. He quotes Greta Garbo when they first meet, admits he saw the actress perform twice as Lady Macbeth to the Princess, and in one scene pointedly thanks her for "playing your part". He even paraphrases her lines as Lady Macbeth when she shows up with the dagger.
Poirot:Why did you take this dagger from the place?
When Ratchett first speaks to Poirot, he claims that he has enemies. Poirot notes that a man in a position to have enemies is unlikely to have only one. The Reveal is that there was indeed not "only one" killer.
Let Off by the Detective: With the victim being an Asshole Victim of the highest order, Poirot rationalises that his murder meant justice was done. Instead of revealing the real solution to the police, he manages to come up with a plausible enough explanation involving an unknown assassin that doesn't incriminate the guilty party. Those in authority accept this explanation rather than go through the political, legal, and publicity nightmare of prosecuting twelve people (some of whom are wealthy and powerful) for the murder of said Asshole Victim of the highest order. In the 2010 version he only does so after an immense amount of soul-searching, and even then it's clear from his expression that he's not sure if he's done the right thing.
Off on a Technicality: How Ratchett managed to walk free after the killing of Daisy Armstrong. He still recognised that the public would have torn him apart the moment he left court, hence why he fled America and changed his name.
Orgy of Evidence: Not only are there a dozen suspects with a connection to the victim, but there are also a misplaced match, a pipe cleaner, a handkerchief, a button from a railway worker's uniform, a watch broken at entirely the wrong time, and sightings of a woman in a red kimono. Poirot, to his credit, dismisses most of these fairly quickly as Red Herrings.
Pay Evil unto Evil: The victim had been guilty of the kidnapping and murder of a small child years before. Poirot finds the man is so deserving of his murder that he decides not to turn the murderer over to the police, and even offers them a theory of how the murderer escaped the train which is as plausible as it is false.
Pinkerton Detective: Cyrus Hardman in the 1974 film version. The original novel has him employed by McNeil's.
Red Herring: Literally referred to by Poirot during The Reveal : he points out that the mafia member and the red kimono were just "red herrings to confuse and deceive him", and even describes the night of the murder as the "night of the red herrings". See Orgy of Evidence.
Ripped from the Headlines: The kidnapping and murder of heiress Daisy Armstrong is very much based on the Lindbergh kidnapping case.
Sand in My Eyes: The reaction that the snow was dazzling a suspect's eyes actually turns out to be a clue.
Seamless Spontaneous Lie: Everyone on the train was a part of the murder. They had to make up several lies to throw Poirot off their trail. This was something like a dozen people. That kept up a lie under the scrutiny of Poirot. On a train in the middle of the Alps.
Though not so much spontaneous, as they intentionally planned their stories so that pretty much everyone had an alibi with someone who would have no reason to lie about it (who would suspect Arbuthnot and Macqueen to be in it together, or Mrs. Hubbard and Greta, or Foscarelli and Masterman). And the stories do have flaws, just not immediately obvious ones.
Sherlock Scan: An odd example - Poirot is somehow able to intuit that a suspect previously worked as a cook thanks to his "nose for fine dining." In the 2010 adaptation, the clue is instead that he overheard them giving detailed instructions to the waiter when ordering dinner.