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->"A person's a person, no matter how small."

''Horton Hears a Who!'' is a 1954 children's book by Creator/DrSeuss, adapted into a 1970 {{animated s|hows}}pecial by MGM Animation/Visual Arts (the studio responsible for the classic animated adaptation of ''WesternAnimation/HowTheGrinchStoleChristmas'') and a 2008 animated film from Creator/BlueSkyStudios (the creators of ''IceAge''). The book's plot also makes up a sizable part of the plot of the stage musical ''Theatre/{{Seussical}}''. It was dedicated to a Japanese friend, Mitsugi Nakamura. In fact, Seuss intended for the story to be a metaphor for the American occupation of Japan after UsefulNotes/WorldWarII.

Rare for Seuss, this book is a sequel (to ''Literature/HortonHatchesTheEgg).''

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!!This book and its adaptations provides examples of:

* AcousticLicense: The climax of the story has the entire worldwide (speckwide?) population of Whos making as much noise as they can in a last ditch attempt to be heard by animals other than Horton. It doesn't work, until the addition of [[spoiler:the shout of one small child]] makes all the difference.
* AdaptationExpansion: The movie.
* AscendedExtra: Jojo in both the movie and ''Seussical''.
* CassandraTruth: Horton's practically the TropeCodifier for people who read this book as a child.
** Same goes for the main Who, who can't get anyone else in town to believe they are on a speck of dust until the bird drops the clover.
* {{Cloudcuckoolander}}: Subverted in the book and in ''Seussical'' because everyone in the Jungle of Nool thinks that Horton is a tad off his rocker for hearing a Who.
* DefeatMeansFriendship
* {{Determinator}}: Horton. Sour kangaroos, weak bridges, open valleys, villainous vultures, flat cliffs, snowy mountain tops, ''losing the speck amongst miles of similar-looking clovers'', and mobs of animals trying to rope and cage him, will. Not. Make. Him. ''Stop.'' Physically or emotionally - despite people telling him to stop believing in the Whos, Horton doesn't stop.
** An elephant's faithful, one hundred percent.
** The Sour Kangaroo is equally determined to ''stop'' Horton, to the point of siccing an angry mob on him.
* DisproportionateRetribution: Sour Kangaroo is the queen of this.
* EasilyForgiven: All the "villains".
* EmoTeen: Jojo.
* HappilyEverAfter
* HereWeGoAgain: The ending to the animated special.
* HypocriticalHumor: "He has the nerve to call me a boob? I would never call somebody a boob. ''HE'S'' a boob!"
* KarmaHoudini: Sour Kangaroo, especially in the movie.
** Of course. Horton's [[{{Forgiveness}} cool like that]].
*** WordOfGod says that in the movie she was originally going to get much better comeuppence in the form of all the other animals turning their back on her but the writers decided to cut that out saying that "Dr. Seuss wasn't big on revenge".
* {{Lilliputians}}: Whos, who are only a few microns high.
* ManiacMonkeys: The Wickersham brothers.
* MindScrew: ''What the hell are you, Katie!?''
** WordOfGod says she's a baby yak.
*** [[ComicallyMissingThePoint That was obviously not the problem.]]
* MisplacedWildlife: Kangaroo.
* {{Narrator}}
* NerdsAreSexy[=/=]HotScientist: Dr. Larue.
* OneSteveLimit: The Two Vlads.
* OnlySaneMan: In the movie, Rudy [the joey] and possibly Jojo as well.
* RecursiveReality: Horton discovers a whole world in a tiny dust speck. The TV special of it has an ending in which the main Who finds another dust speck with its own world. At one point in The Movie, Horton wonders whether the universe he inhabits could itself exist as a speck of dust to another universe.
* RepetitiveName: Vlad Vladikoff.
* RidiculouslyCuteCritter: Again, Katie.
* SilentSnarker: Jojo, [[spoiler:up until [[SuddenlyVoiced he begins talking again]].]]
* SkywardScream: In all versions of the story, [[spoiler:Jojo's shout ("YOPP!") is the final sound that pushes the sounds of the Whos bursting out of the clover.]]

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!!The 1970s cartoon adaptation provides examples of:

* ArsonMurderAndJaywalking: The Wickersham Brothers claim that Horton will "steal our jewels and shut our schools and even change our football rules."
* TheCameo:
** [[spoiler:The Grinch!]] In the 1970s TV version he makes a cameo in the Who chorus near the end.
** And the modern version: Watch the new version of the "We Are Here" chorus - if that's not the Grinch playing that tiny set of pan pipes, he's one heck of a doppelganger.
** He also makes a cameo in ''Seussical''.
* StockFootage: The 1970 special uses this quite a bit.
* VillainSong: The Wickersham Brothers get perhaps the [[EarWorm catchiest number]] in the 1970 special. They also [[AngryMobSong do some chanting when caging Horton and trying to boil the clover]].
* WitchHunt: The Wickersham Brothers in the 1970s version treat Horton like a RedScare. "You're trying to stir up discontent, and take the reins of government..."

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!!The 2008 adaptation provides examples of:

* AdaptationalVillainy: In the original story, Kangaroo was a WellIntentionedExtremist who was grumpy, but not really much of a villain. Here, she's a straight-up sadist who cares more about her own ego than the other jungle animals, and seems to have a lot more fun in torturing Horton than she should. Not to mention being portrayed as borderline abusive toward the children that she claims to be [[ThinkOfTheChildren protecting]].
** Look at the way the animals are cowering in fear of her at the beginning. Did she previously [[FridgeHorror abuse them in the past?]]
** And possibly genocidal (toward the Who's) as well. Notice how she tried to take the clover away from Horton ''even after she heard the Who's "we are here".''
** [[FeatheredFiend Vlad Vladikoff]] as well. In the original story, he didn't have much of a role. He simply just carried the clover off and dropped it. In the film, on the other hand, he's upgraded to a genuinely terrifying, dangerous, and feared character, with [[ToothyBird sharp teeth]] and a sadistic sense of humor. Just look at his [[SlasherSmile gleeful grin]] when he tells Kangaroo to offer her son to him as food.
* ArtShift: Happens twice. The first time is a 2D animated sequence drawn completely in Seuss' distinctive style. The other is an {{Anime}} parody action sequence/daydream, complete with mouth movements that don't match up to the voices.
* BitsOfMeKeepPassingOut: The Mayor is at the dentist when an earthquake (caused by the speck the Whos all inhabit moving) occurs, and the Novocaine needle ends up in his arm, which remains limp and useless for some time afterward.
* BreakoutCharacter: Jojo quickly became the most popular charcter in the film adaptation.
* BrickJoke: [[spoiler:The other Vlad]].
** And Burt from Accounting makes an appearance.
** On the rope bridge, Horton thinks that inhaling deeply will make him lighter. Near the end Katie inhales deeply... and ''floats away''.
* {{Cloudcuckoolander}}:
** Katie.
** Horton himself. Just the sheer fact that Horton is voiced by Creator/JimCarrey in the film qualifies him for this.
* ContinuityNod: Horton's catchphrase in the movie was, of course, imported from ''Horton Hatches the Egg''.
* CrazyEnoughToWork: Horton's plan in the movie is to relocate the Whos to a safer place (since in the adaption Whoville has somehow become unstable). Guess where he chooses? ''A mountain''. Colder climate. Less hospitable terrain. [[StupidityIsTheOnlyOption Yes, he choose a mountain]]. Sour Kangaroo and her vacant pouch would have been a more sensible choice (and poetic, going from destroyer to protector of the Whos) after her [[HeelFaceTurn Heel-face turn]].
* CreepyChild: Katie in the movie. "Aaah..."
* CrowdSong: The end of the movie.
* EasilyForgiven: The animals in the jungle of Nool. Parodied when Horton says he couldn't have done it without their utter lack of support and naked aggression.
* GadgeteerGenius: Jojo has a natural talent for creating machines that make a lot of noise.
* GenreSavvy: While Horton is escaping Vlad the vulture, he briefly loses him and predicts that said vulture will pop out of nowhere eventually. [[spoiler: Guess who's right behind Horton as he says this.]]
** Soon after, he says, "Cool line! Usually I can't think of those things till later."
* GettingCrapPastTheRadar: "Ninety-six daughters and one son." "Busy guy." "''And'' we all share one bathroom. You know how that is."
* {{Goth}}: Jojo shows some shades of this.
* GroinAttack: The mayor gets wedged between a door as a large fishbowl strikes him in the crotch.
** Which is to say nothing of what happens later during the Vlad chase. The Mayor rolls out onto his balcony, hits one of the railing pillars between his legs, then is shoved in further by his desk, a couch and a ''refrigerator''. Safe to say there probably won't be a 98th child.
* HypocriticalHumor: Besides the "Boob" comment above, Sour Kangaroo's claiming for [[ThinkAboutTheChildren the children's safety]], then suddenly punting Katie out of the jungle.
* IgnoredExpert: The Mayor of Whoville.
* ILoveTheSmellOfXInTheMorning:
-->'''Horton:''' I love the smell of bananas in the morning!
* KnightTemplarParent: Kangaroo
* LargeHam: Subdued, compared to his other performances, but Jim Carrey as Horton.
* MediumShiftGag: The previously AllCGICartoon briefly shifts into an {{Anime}} {{parody}} as Horton imagines himself as a ninja sworn to protect the tiny world on the clover.
** There's even a brief traditionally animated segment drawn in Dr. Seuss' style when Horton imagines a Who on the speck "calling for help".
* MyBelovedSmother: Sour Kangaroo is this to Rudy, refusing to let him leave her pouch.
* OddNameOut: Ninety-six of the Mayor's ninety-seven children all have names beginning with the letter H. Jojo, the Mayor's only son, is the OddNameOut.
* OhCrap: Not immediately, but eventuallly Horton catches on.
-->'''Horton:''' Oh! I see! It's an angry mob! Coming right... for... (Starts getting it) Oh no...
* OutnumberedSibling: The Mayor has ninety-six daughters, and only one son, Jojo.
* RopeBridge: Horton has to cross one on his way to Mt. Nool.
* ShamingTheMob: Subverted, along with the RousingSpeech.
* ShoutOut: Several to various Dr. Seuss works.
** One Who has a blue hat similar to the one worn by Literature/TheCatInTheHat, as well as a few of The Cat's mannerisms (including a smaller version of himself underneath his hat).
** The Mayor and his family eat Literature/GreenEggsAndHam for breakfast.
** The city council seems to consist of [[Literature/HowTheGrinchStoleChristmas Grinches]].
** Rudy's imaginary clover friend is named "Thidwick", a refrence to Thidwick the Moose.
** The Mayor has a red fish as a pet, possibly a refrence to One Fish Two Fish Red Fish Blue Fish.
** One of the portraits of past mayors was [[spoiler:[[AuthorAvatar Dr. Seuss]]]] himself (specifically, the one of Ned's father)!
* StealthPun: In the original story, Vlad was described as a "black-bottomed eagle". Here, he looks more like a vulture, without feathers on his head. So wait, does that make him a [[spoiler:[[{{Pun}} bald eagle]]]]?
* StrawHypocrite: Sour Kangaroo, obviously cares more about putting down others than actually caring about [[ThinkAboutTheChildren the children.]] It's followed by kicking Katie across the jungle.
* SuddenMusicalEnding: And ''how.'' "I Can't Fight This Feeling Anymore" out of nowhere.
* SuspiciouslySpecificDenial: The Mayor constantly reassures the Doctor that he absolutely ''did not'' have a conversation with an elephant in the sky.
* TakeThat: One of the scriptwriters must not have had a high opinion of home-schooling.
* ThinkOfTheChildren: In the 2008 movie, the kangaroo rallies all the other animals in the jungle against Horton with this cry.
* ToothyBird: Vlad Vladikoff, a toothy vulture.
* TotallyRadical: When the Mayor tries to relate to Jojo at the beginning of the film. It fails.
* TravelingPipeBulge: This happens when Horton's voice first travels down the pipe to the mayor's office.
* TreeBuchet: How Horton gets rid of Vlad in the movie.
* TremorTrampoline: Happens to the world of Whoville several times; after all, a small bump from Horton's perpective is a ''big'' bump from the Whos perspective.
** One time when it happened, was while a house was under construction; when everything was bounced skywards, the house came back down ''fully built''.
* WhatMeasureIsANonCute: Subverted; the main villain is a kangaroo.
* WellDoneSonGuy: Jojo's main reason for never talking is that he thinks that if he does, then he'll disappoint his father.
* WellIntentionedExtremist: Kangaroo is actually a subversion. It's pretty obvious that she's enforcing her rules for the sake of her own ego instead of actually protecting anybody (She goes on about protecting the children, [[HypocriticalHumor then kicks Katie]] [[{{Jerkass}} clear across the jungle.]])
* WitchHunt: There's a bit of this in the 2008 movie as well.
--> '''Kangaroo:''' If the children hear stories about worlds beyond the jungle, they'll start to question authority! Which leads to defiance, which lead to ANARCHY!
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