->'''Bruno:''' It's so simple, too. A couple of fellows meet accidentally, like you and me. No connection between them at all. Never saw each other before. Each of them has somebody he'd like to get rid of, but he can't murder the person he wants to get rid of. He'll get caught. So they swap murders.\\
'''Guy:''' Swap murders?\\
'''Bruno:''' Each fellow does the other fellow's murder. Then there is nothing to connect them. The one who had the motive isn't there. Each fellow murders a total stranger. Like you do my murder and I do yours.\\
'''Guy:''' We're coming into my station.\\
'''Bruno:''' For example, your wife, my father. Criss-cross.
-->-- ''Strangers on a Train''

A 1951 Creator/AlfredHitchcock thriller starring Farley Granger and Robert Walker. Guy Haines (Granger), an amateur tennis star, meets the eccentric Bruno Anthony (Walker) on a train. Bruno has read about Guy's romantic troubles in the paper, and suggests that he might want to... [[MurderIsTheBestSolution dispose of his wife]], the unfaithful Mrs. Miriam Joyce Haines (Kasey Rogers under the alias "Laura Elliot"), so he can marry Anne Morton (Ruth Roman), the daughter of a U.S. Senator. Bruno tells Guy of his own unhappiness with his father, and outlines his plot for the perfect murder: [[StrangersOnATrainPlotMurder two strangers who both have someone they want dead "exchange murders"]]. Guy laughs the whole thing off and gets off the train but, as he learns a few days later, Bruno wasn't joking.

The movie was based on a novel by Patricia Highsmith (of ''Literature/{{Ripliad}}'' fame) and had a screenplay originally written by Creator/RaymondChandler (before he was fired and replaced). The book and the movie are the {{Trope Namer|s}}, {{Trope Maker|s}}, and TropeCodifier for StrangersOnATrainPlotMurder, although there's a lot more to the story than [[AllThereIsToKnowAboutTheCryingGame just that one trope]]. The 1987 comedy ''Film/ThrowMommaFromTheTrain'' is part parody, part remake and part homage of this film.

A remake directed by Creator/DavidFincher and starring Creator/BenAffleck, simply titled ''Strangers'', was announced in 2015.

!!This film provides examples of:

* AbsentMindedProfessor: Collins, the drunken mathematician on the train. It's his forgetfulness that kills Guy's alibi.
* AdaptationalHeroism: In the original book, Guy tragically succumbed to Bruno's pressure to murder his father.
* AdaptationalNameChange: Charles Anthony Bruno became Bruno Anthony, while Anne Faulkner became Anne Morton.
* AmbiguouslyGay: Both lead characters. Bruno, the SissyVillain, is almost overt about it; Guy (whose actor was openly bisexual) is more of a "sexually ambiguous" ingenue. The film, with an up-and-coming man with a future in politics who gets involved with another man who acts in a flirtatious manner, has been read as commentary on the anti-homosexual hysteria of the 1950s, when the [[RedScare HUAC]] was on a witch hunt for "sex perverts" and other subversives in the government.
* AmusementPark: The scene of [[spoiler:Miriam's murder]] and of the film's climax.
* AngryGuardDog: Subverted. After sneaking into the Anthony house late at night to find Bruno's father and [[spoiler:warn him]], Guy encounters a growling Great Dane on the stairs. However, as he gets closer the dog comes up and licks his hand.
* AssholeVictim: Miriam Haines
** JerkassWoobie: In the book. She still refuses Guy a divorce and tries to join him in Palm Beach, where Guy is supposed to be remodelling a country club, as a way of cutting in on his earnings and/or convincing his co-workers that he's the father of her baby, thereby forcing him to support the child. However, Miriam suffers a fall in her own home and miscarries, which leaves Guy perfectly free to aggressively pursue a divorce and means that Bruno had absolutely no reason at all to kill Miriam.
* AxCrazy: Bruno
* BadassBystander: The random CoolOldGuy who volunteers to stop the speeding carousel...by crawling underneath it to get to the mechanism at the center.
* BookEnds: In the final scene, a stranger--a clergyman--recognizes Guy on a train and tries to strike up a conversation with him. He and Ann respond by [[WeAreNotGoingThroughThatAgain getting up and moving to another car]].
* ClutchingHandTrap: Bruno, a remorseless murderer, gets his arm stuck in a drainage hole by the sidewalk. This is played for suspense, as it helps buy time for Guy to finish his scheduled tennis match ([[spoiler:though Bruno makes it to the amusement park first anyway]]), though it does have Alfred Hitchcock's trademark dark humor.
* CreatorCameo: Hitchcock appears lugging around an upright bass the first time Guy gets off the train.
* DepravedHomosexual: If Bruno is gay he definitely fits this trope.
* DefiantToTheEnd: In the face of a witness to his murder, his possession of incriminating evidence, and his [[spoiler: imminent death]], Bruno ''never'' stops trying to [[spoiler: frame Guy.]]
* TheDitz: Bruno's mother. Anne had to bluntly spell it out for her that her baby boy killed a woman, for his mother to ask if ''Bruno'' told her any of this and if not, that isn't true.
* DoesThisRemindYouOfAnything: Much like in ''Film/ShadowOfADoubt'', there is a pre-occupation with strangulation in this film, Bruno strangles Miriam and Guy expresses desire to strangle Miriam. Their desire may very well be a response to subconscious sexual urges, namely that of erotic asphyxiation.
** It's also important to note that Miriam, declared a tramp and adulteress by numerous characters before and after her murder, is double teamed by two men in the tunnel of love and goes to the secluded island, which is referred to as a hot spot for 'smoochers', with them. For comparison, in the book at least one of her companions is noted to be her brother.
* FauxAffablyEvil: Bruno
* FeetFirstIntroduction: For both Bruno and Guy, the first of many times the movie contrasts the two.
* {{Foil}}: Bruno and Guy, very intentional (see NumerologicalMotif below).
* {{Homage}}: ''Film/ThrowMommaFromTheTrain''.
* IJustShotMarvinInTheFace: The cops at the end shoot at Guy (when he's running into a crowd of children, no less) instead of just chasing after him. Nobody seems to care that one of the shots hits and kills the merry-go-round attendant.
** Probably because they're too busy caring about the merry-go-round full of people that's [[spoiler:going at a dangerous speed and can't be stopped now that its attendant is gone.]]
* IdenticalStranger: Barbara Morton and Miriam Joyce Haines. Not quite identical, but similar enough that it becomes a plot point.
* ImperiledInPregnancy: Miriam is pregnant at the time of her murder. (In the book, she has suffered a miscarriage shortly before that point.) Oddly, nobody seems particularly concerned by this fact, perhaps because she's an AssholeVictim.
* InformedAttribute: Bruno claims his father is a horrible person, but we have only the word of a madman to go on. Indeed, the one time we see him he appears genuinely concerned for his son's well-being.
** Moreso in the novel, where the aforementioned scene never takes place and the reader knows nothing about Bruno's father right up until [[spoiler: Guy kills him]], at which point a private detective in Bruno's father's employ tells Bruno that if he honestly thinks his father didn't love him then he really didn't know him at all.
* KarmicDeath: [[spoiler:Bruno.]]
* MacGuffin: Guy's lighter.
* {{Meganekko}}: Ann's younger sister, Barbara "Babs" Morton (played by Hitchcock's daughter Patricia).
* MommyIssues: Bruno. More so in the book where Bruno's mother is described as moderately attractive and has a lot of male friends. In the film she's fairly old and delusional.
* MyGodYouAreSerious: Guy's reaction when he learns about Bruno [[spoiler:killing his wife]].
* NumerologicalMotif: The number two and the concepts of doubles and doppelgangers are both important in this movie.
** The theme of crosses and ''double'' crossing could fit under here as well.
* OedipusComplex: Bruno wants to kill his father and is very... ''close'' with his mother. Need we say more?
* ThePerfectCrime
* PsychologicalHorror: Not as much compared to some Hitchcock movies, but it's certainly there. While he's kind of funny most of the time, there are moments when Bruno is ''terrifying''.
* PsychopathicManchild: Bruno
* ReflectiveEyes: Or Reflective Eyeglasses, anyway; we see [[spoiler:Bruno strangle Miriam]] in them after they're knocked to the ground.
* SarcasmBlind: Guy's reaction to Bruno's plan is bewilderment, and when Bruno asks if he thinks it is a good plan, Guy sarcastically responds in the affirmative.
* SissyVillain: Bruno
* SoundtrackDissonance: [[spoiler:Miriam's murder]] is accompanied by jaunty carousel music in the background (which actually goes [[NumerologicalMotif twice as fast]] as it does in the rest of the amusement park scenes).
* SparedByTheAdaptation: Guy actually kills Bruno's father in the book. In the film, he doesn't go through with it.
* StrangersOnATrainPlotMurder: {{Trope Namer|s}}, and an UnbuiltTrope: Guy laughs Bruno's suggestion off as a joke, only to discover that Bruno is all too serious. [[spoiler:In the end, Guy doesn't go through with it -- in the movie, at least.]]
* VillainBall: Bruno all but outright tells Anne what he's going to do to [[spoiler:frame Guy]], just to rub Guy's nose in it, even though it gives Guy a chance to stop him.
* YoureInsane: Variations of the phrase are frequently used by Guy to describe Bruno, much to his chagrin.