A 1938 film starring Margaret Lockwood and Creator/MichaelRedgrave, ''The Lady Vanishes'' is one of the last films directed by Creator/AlfredHitchcock before he left his native Britain and went off to Hollywood.

After receiving a nasty bump on the head, Iris Henderson (Lockwood), a young English socialite who's on her way back home from a vacation tour, meets Miss Froy (May Whitty), a nice middle-aged lady, on board a train travelling through Bandrika, a fictional country somewhere in central Europe. They get on nicely for a while, when suddenly... the lady vanishes ([[ExactlyWhatItSaysOnTheTin what a twist]]). Iris and the caddish-yet-loveable Gilbert (Redgrave) promptly try to locate her - but nobody seems to remember seeing Miss Froy. Did Iris just make her up? Or is there foul play at work?

All right, there ''is'' foul play. But there's also a ScrewballComedy relationship between Iris and Gilbert. And two hilariously over-the-top Englishmen obsessed with cricket. This is probably one of Hitchcock's nicer films -- think ''Film/{{The 39 Steps|1935}}''.

The film was remade in 1979, with Creator/AngelaLansbury in the title role, and a TV movie version aired on the BBC in 2013. Unofficially, the Creator/JodieFoster film ''Film/{{Flightplan}}'' bears quite a few similarities.
!!This film provides examples of:

* AffablyEvil: Dr. Hartz seems like he's genuinely a nice guy, even despite being a Nazi assassin. He even gleefully wishes the heroes good luck at the end after they escape him.
* ApatheticCitizens: Half the people who say they never saw Miss Froy aren't even part of the conspiracy, they just don't want to get involved for reasons of their own.
* ArrangedMarriage: Iris is supposed to enter into one as soon as she returns to England. {{Defied|Trope}} when she decides to marry Gilbert instead.
* BadHabits: Dr. Hartz' cohort dresses as a nun throughout the movie. She makes a mistake in her disguise, however: she wears high heels, which would never be worn as a part of a real nun's vestments.
* BelligerentSexualTension: Iris and Gilbert.
* TheBigDamnKiss: [[spoiler: Gilbert]] practically sweeps [[spoiler: Iris]] into his arms for their FirstKiss in the cab when it becomes evident to both of them that [[spoiler: Iris]] has thought the better of marrying her [[UpperClassTwit titled but idiotic-looking]] fiancé.
* BlackmailIsSuchAnUglyWord: [[spoiler: Miss Froy thinks "spy" is an awful term]].
* CassandraTruth: The movie shows shades of this early on as Iris tries desperately to convince everyone that Miss Froy exists.
* CasualDangerDialogue: Charters and Caldicott keep up their customary banter even during the climactic shootout.
* ChekhovsGun: The tune the guitarist is playing is the code that Froy was [[BringNewsBack bringing home]].
* ChekhovsGunman: The guitar player near the beginning.
* CondensationClue: Iris sees Miss Froy's previously written name.
* CouldntFindAPen: Miss Froy writes her name on the train window.
* CoverIdentityAnomaly: The clue that gives away Dr. Hartz's assistant: real nuns never wear high heels as part of their vestments.
* CreatorCameo: Hitchcock, near the beginning of his practice of making a cameo in every film, pops up for a few seconds at the station at the end.
* DoomedDefeatist: Todhunter, who also proves to be TooDumbToLive.
* EvilAllAlong: Dr. Hartz, a kindly doctor who tries to help Iris out after Froy's disappearance. Oh, and he's secretly a paid assassin working for the Nazis, not to mention the one who kidnapped Miss Froy to begin with.
* FireForgedFriends: Iris and Gilbert.
* HandOfDeath: A pair dispatches the guitar player.
* HeelFaceTurn: The nun who worked with Dr. Hartz. Apparently she's okay with all of the other things the Nazis have her do, but murdering a nice old lady (who happens to be a British spy) is [[EvenEvilHasStandards going too far]].
* ImpairmentShot: Iris on the train, after a flower pot has been pushed off a windowsill and hit her on the head.
* ImperialStormtrooperMarksmanshipAcademy: In the shootout during the film's climax several villainous mooks are killed while very few of the train's passengers are killed. Justified in that the people on the train had cover while the mooks that died were in the open. The passengers who died ([[DisposablePilot both conductors]] and Todhunter) were also in the open when they got shot to death.
* ItWasHereISwear: A running theme with Iris trying to prove the existence of the old lady after she's gone.
* JerkWithAHeartOfGold: Gilbert rather rudely sidelines Iris's legitimate concerns about his constant noisemaking upstairs and freaks her out by passive-aggressively move into her hotel space, but when he sees her raving about Froy's disappearance, he's genuinely concerned and sets out to help her.
* LetsGetDangerous: Caldicott and Charters spend most of the film being ''beyond'' useless. Then when they're finally convinced that the train is under siege by Nazis, they both grab guns and start putting up one hell of a defense.
* MacGuffin: The tune that Miss Froy teaches Gilbert is actually a coded message. We never entirely learn the significance of it except that it has something to do with a treaty between two European nations.
* MissingTheGoodStuff: Caldicott and Charters spend the whole film looking forward to getting back to London for the end of a big cricket test match, only to find that it's been rained out.
* NeutralFemale: {{Defied| Trope}}. A fight scene between Gilbert and one of the conspirators starts out with Iris standing on the sidelines before Gilbert tells her "don't just stand there like a referee, cooperate." She does help and actually ends up being the one to disarm and knock out the bad guy.
* PlotBasedVoiceCancellation: Miss Froy tries to introduce herself to Iris but loud train noises cancel out what she is saying. This prompts her to write her name on the window, which turns into a ChekhovsGun later when the Iris sees the writing again, proving to herself that she was not imagining their encounter.
* PrettyInMink: Iris wears one in the first part of the movie.
* {{Ruritania}}: Bandrinka. They stop in two towns, Dravtka and Morsken.
* SeriousBusiness: Murder, disappearances, soldiers with guns, ho hum. But if Caldicott and Charters can't find out today's cricket scores? Really, that's too much!
* ShoutOut: To Franchise/SherlockHolmes. When Gilbert tells Iris his theory about the disappearance he puts on a deerstalker hat and picks up a pipe. He even refers to Iris as "Watson."
* SpannerInTheWorks: Iris isn't stupid, but she is completely unaware of the conspiracy until the end. She still manages to destroy the conspiracy just because she won't stop insisting that Miss Froy exists.
* SuitWithVestedInterests: Caldicott and Charters form a peculiar example from before the age of the monster attack movie but their self-interested obliviousness matches well with the behaviour of a tourist-town mayor not wanting to close the beaches on the fourth of July... but for cricket.
* ThoseTwoGuys: Caldicott and Charters. Which became ThoseTwoActors for Basil Radford and Naunton Wayne. Not only did they reprise their roles two years later in Carol Reed's ''Film/NightTrainToMunich'', but they appeared together (as differently-named but virtually identical characters) in numerous other film and radio productions from 1940 until Radford's death in 1952.
* ThrillerOnTheExpress
* TooDumbToLive: The train car that the heroes are on has been diverted to the middle of nowhere and surrounded by armed Nazi soldiers. It's been made clear already that the soldiers aren't interested in working things out, which the passengers discovered when one of them tried to talk to the soldiers and got shot in the hand. Todhunter, in spite of all of this, still tries surrendering. He is promptly shot dead.
* WorthyOpponent: In a scene that's quite weird to watch these days, Nazi spy Dr. Hartz cheerfully accepts his defeat and wishes our heroes good luck.

!!Examples specific to the remakes:

* GenreShift: The 2013 BBC adaptation is a serious psychological thriller. That is not to say that the original 1938 film did not have a serious thriller plot, but it also contained a screwball comedy subplot and much more humor in general. In the original, the foreignness of many of the characters is played for comedy, while in the remake it is used to heighten Iris's sense of isolation and fear.
* ImpairmentShot: The 2013 BBC version uses this as a drugged Iris is being taken off the train.
* TheRemake:
** By Hammer (yes, ''[[Film/HammerHorror that]]'' Hammer) in 1979.
** Another one was made in 2012 and broadcast by the BBC in 2013.