An author, developer, or a group of them start with a basic idea, and from there start building a new work intended to be released to the public, but sometimes these author(s) may see that their creation isn't working like they intended to, it's missing a little ''something'' in it. Maybe the creators are not very talented in the genre or media they used to start their work, maybe those just don't, or flat out can't, show the work the way they intended to, or maybe it's just for a [[ExecutiveMeddling meddling executive]] getting involved.

Whatever the reason, they see that the bases they have chosen for their work just aren't working the way they want to, so it's time to change one or more of these bases before they release anything.

This can come in two flavors:

* '''Genre shift:''' The work keeps its grounds on the same media, but changes its style to other of the many genres inside that media, like from Comedy to Drama in {{Theater}}, or a Platformer to Action Adventure in VideoGames.
* '''Media Shift:''' Unusual but not unheard of, this one generally occurs during the first moments of the work's creation, and regularly means that the author's goal for this work just wasn't expressed well in the media chosen. For example, the author could have started with his work in written media, but then (s)he sees that without visuals it feels incomplete and/or that a fitting BGM could do a much better job conveying the feelings that (s)he intends to show; or maybe started with some sort of visual media, but later thinks that using more reader's interpretation and less "this is how it was and looked like" is a better option for his intentions.

Don't confuse with GenreShift, CerebusSyndrome, ReverseCerebusSyndrome, and CerebusRollercoaster, which are changes during a work's run instead of before its release. Subtrope of WhatCouldHaveBeen.
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!! Examples:

[[foldercontrol]]

[[folder: Anime And Manga ]]

* ''Anime/MagicalGirlLyricalNanoha'' was originally intended to be a straight MagicalGirl series, but ended up somewhat closer to HumongousMecha show with cute girls once it was released.
* ''Manga/YuGiOh'' was originally intended to be a straight-up horror manga, before transitioning to the game/card battle series it's recognized as.

[[/folder]]

[[folder: Comic Books ]]

* ''The Griff'' was written by Creator/ChristopherMoore and Ian Corson. It started as another Moore novel, but when he realized the idea was too visually dependent for the written word he set it aside - until the opportunity to make a graphic novel arose.

[[/folder]]

[[folder: Fan Works ]]

* ''WebAnimation/TurnaboutStorm'' started out as a written fanfiction, but as it progressed evolved to an attempt at a game in order to be able to put music in it, then to a radio play, and finally to it settled with ''VisualNovel/AceAttorney'' game-walkthrough-like videos so visual elements could be added.
* Quite a lot of ''Fanfic/TheNextFrontier'' had been written before its creator had firmly decided just what it was going to be a crossover ''with''. (''WesternAnimation/MyLittlePonyFriendshipIsMagic'' was the other possibility.) The decision to make TheReveal of the crossover an invoked ShockingSwerve was therefore something of a ThrowItIn moment.

[[/folder]]

[[folder: Film - Animated]]
* ''Disney/TheEmperorsNewGroove'' was originally conceived as a dark musical film rather than a lighthearted comedy with only one or two songs. And [[BigBad Yzma]] was originally going to have her own song.
* ''WesternAnimation/QuestForCamelot'' was written to be a serious PG-13 animated film. During development, producers decided to amp up the slapstick and make it more kid-oriented. They also turned it into a musical - with the result that nearly every cast member has a NonSingingVoice.
[[/folder]]

[[folder: Film - Live Action ]]

* ''Film/CoolWorld'' was originally intended to be a horror film but ExecutiveMeddling demanded a more family-friendly plot and rewrote it. This explains the resultant tonal inconsistency.
* ''Film/DrStrangelove'' was originally meant to be a straight drama, much like the original novel, but Creator/StanleyKubrick found the situations so ridiculous and over-the-top that he decided to [[PlayedForLaughs play it for]] [[DarkComedy dark laughs]].
* ''Film/MulhollandDrive'' was originally going to be a TV series. The first two-thirds (made for TV) are nowhere near as surreal or adult-oriented as the climax, made to wrap everything up as a film.
* ''Film/GoodWillHunting'' was originally conceived of by Matt Damon and Ben Affleck as a thriller, before the Weinsteins encouraged them to instead emphasize the relationship between Will and his psychologist.
* Seen in the Korean movie ''Windstruck'' (the loose prequel to ''Film/MySassyGirl''), which veered from RomCom to Fantasy to Tragedy and back.
* ''Film/{{Zombieland}}'' was originally intended as a TV series.
* ''Dear Diary'' - a ShortFilm - was a sitcom pilot that wasn't picked up. Won an [[UsefulNotes/AcademyAward Oscar]] for Best Short Subject.
* ''Film/{{Beetlejuice}}'' was originally supposed to be a horror movie, but was changed to a supernatural comedy.
* ''Film/{{Evolution}}'' was going to be a serious sci-fi movie but became a sci-fi comedy.
* ''Film/HolidayInn'' was originally to have been produced on Broadway as a plotless revue.
* Jason Friedberg and Aaron Seltzer's ''Film/DisasterMovie'' started life as a ''Film/{{Superbad}}'' parody called "Goodie Two Shoes", but for whatever reason changed to a loose parody of ''Film/{{Cloverfield}}'' in the middle of production.
* In-universe example: in ''Film/ShakespeareInLove'', Shakespeare starts writing a comedy named "Romeo And Ethel, The Pirate's Daughter", which becomes ''Theatre/RomeoAndJuliet''.
* The first draft of ''Film/{{Clerks}}'' was a [[DavidLynch Lynchian]] surreal horror film about a convenience store clerk and the odd characters he meets during the graveyard shift.
* ''Film/BeverlyHillsCop'' was originally a violent action film starring Creator/SylvesterStallone. When he dropped out, it became an Creator/EddieMurphy comedy.
* On a similar note, ''Film/TheGoldenChild'' was originally a serious action-fantasy starring Creator/MelGibson that became a Murphy vehicle.
* ''Film/BigTroubleInLittleChina'' was going to be a western at one stage.
* ''Film/PrettyWoman'' was originally dark drama about prostitution before becoming a romantic comedy.
* ''Film/Jaws3D'' started life as an ''Film/{{Airplane}}''-style parody called ''Jaws 3 People 0''.
* ''Film/BrideWars'' was originally a high school comedy. Which explains so much.
* ''Film/KingCreole'' was originally a serious drama starring Creator/JamesDean. After Dean's death, it was re-tooled into an Creator/ElvisPresley vehicle.
* ''Film/AnnieHall'' was originally a murder-mystery with a comic and romantic subplot. Creator/WoodyAllen later resurrected the idea for ''Film/ManhattanMurderMystery''. At one point, the film was also a period comedy set in VictorianLondon.
* Creator/FrancisFordCoppola originally envisioned ''Film/TheConversation'' as a horror film.
* Similar to the above, Creator/ChristopherNolan originally envisioned ''Film/{{Inception}}'' as a horror film.
* ''Film/CasinoRoyale1967'' was supposed to be a serious adaptation of the novel and proper Franchise/JamesBond film to compete with the proper series. When the filmmakers couldn't get Creator/SeanConnery, it became a spoof.
* ''Film/TheCannonballRun'' was originally a serious action film starring Creator/SteveMcQueen. Upon McQueen's death, it became a Creator/BurtReynolds comedy.
* According to legend, Creator/StevenSpielberg considered making ''Film/NineteenFortyOne'' a musical.
* ''Film/TheCrow'' was almost a musical starring Music/MichaelJackson. Seriously.
* Creator/OliverStone was asked to direct ''Film/ConanTheBarbarian''. His version would have taken place in post-apocalyptic Earth rather than the fantasy setting of the stories.
* ''Film/FaceOff'' was originally a science-fiction film.
* ''Film/WillyWonkaAndTheChocolateFactory'' was made a musical during production. The director was against this, but the producers convinced him by pointing out the success of ''Film/MaryPoppins'' and ''Film/TheWizardOfOz''.
* ''Film/TheSlumberPartyMassacre'' was originally written as a parody of the slasher genre, but it was filmed as a straight horror film.
* ''Film/AfterEarth'' started life as a story about a father and son crashing their car in the mountains or some remote region, with the son having to go out and get rescue for his father.
* Conrad Ball originally wrote ''Film/AmericanBeauty'' as a play.
* Creator/MelBrooks originally conceived ''Film/TheProducers'' as a non-musical play, but realized it required too many set changes. He then played with the idea of it as a book, but it had too much dialogue. Eventually, he realized it could only work as a movie.
* Creator/TommyWiseau originally wrote ''Film/TheRoom'' as a play. The title comes from the intent that it would only take place in the one room. He supposedly then adapted the play into a 500-page book, which he was unable to get published.
* ''Film/TheThreeStooges'' film was originally going to be a {{Biopic}} of the comedy trio.
* ''Film/HollywoodHomicide'' was originally going to be a drama before Suge Knight complained to the producers. The film was subsequently turned into a comedy.
* ''Film/MissPettigrewLivesForADay'' was planned as a musical headlined by Billie Burke as the titular character. Production was cancelled due to World War II and it didn't get made until ''2008'' - where it was now a GenreThrowback to ScrewballComedy.
* ''{{Film/Hook}}'' was planned as a musical, with songs written by Michael Jackson. Two songs do remain though, one sung by the Lost Boys in their introduction and another by Maggie to the pirates.
* ''Film/AlienResurrection'' was written as a {{Camp}} parody of the ''{{Franchise/Alien}}'' films. Director Jean Pierre Jeunet decided to play it straight.
* ''{{Film/Showgirls}}'' was envisioned as a dark, proto-feminist satire on the lives of Vegas showgirls. Along the way it became a notoriously {{Camp}} exploitation film. ''Film/MagicMike'' is closer to what it was originally conceived as.
[[/folder]]

[[folder: Literature ]]
* ''Literature/FearAndLoathingInLasVegas'' by Hunter S. Thompson was originally just going to be a straight series of articles covering a motorcycle race in Las Vegas, before becoming the weird, wacky, genre-defining whatever-it-is that it became.
* Creator/StephenKing:
** He admitted that he didn't know where ''Literature/{{Christine}}'' or his short story "The Library Policeman" were going when he wrote the first several pages. Both started out considerably lighter and more comedic than they ended up. "Literature/TheMist" and "Literature/AptPupil" underwent shifts from short story to novella due to a case of "literary diarrhoea".

[[/folder]]

[[folder: Live Action TV ]]

* ''Series/TwentyFour'' was originally conceived as a domestic comedy about a family preparing for a wedding. Seriously.
* ''Series/SapphireAndSteel'' was initially commissioned as a children's fantasy series, but when PJ Hammond's scripts turned out to be significantly scarier than would be acceptable for that, the network rethought the idea instead of demanding rewrites. "Assignment One" still shows some signs of the original intended audience, with the child [=PoV=] characters, use of nursery rhymes as plot points, rather whimsical kids' TV host characterisation of Lead, and [[spoiler: probably the show's most uncomplicatedly happy ending]]. "Assignment Two", however, clearly indicates the shift, with its even more frightening atmosphere, adult subject matter related to war and sexual relationships and a [[spoiler: very grim ending]].
* ''{{Series/Charmed}}'' was thought up as basically a TV version of ''Film/TheCraft'' about three roommates who were witches. Networks weren't really interested in the witchcraft until Constance M Burge made the characters sisters, and it became the SupernaturalSoapOpera it was best known as.
[[/folder]]

[[folder: Music ]]

* Lampshaded in Electric Funstuff's ''The Next Big Thing''. A video game in development changes through every step of the process.
* On Music/BobDylan's 1985 album ''Empire Burlesque'', the album for displayed a surprisingly (for its time) contemporary sound for Dylan. For the song "When The Night Comes Falling From The Sky", it was originally going to be an [[https://www.youtube.com/watch?v=zKCZ8K1gUDs upbeat rock tune]] with [[Music/BruceSpringsteen the members of The E Street Band]] backing him! But when the album was developed, it was drastically rewritten, now sounding like [[https://www.youtube.com/watch?v=M2tIj4Jd_R0 this]]. This song earned Bob Dylan being called [[FanNickname "Disco Dylan"]] when this album came out.

[[/folder]]

[[folder: Theatre ]]

* ''Theatre/{{Company}}'' was originally written by George Furth as a cycle of eleven short plays.
* ''{{Theatre/Wicked}}'' was originally supposed to be an {{Aida}}-esque romance, the core of the story being the relationship between Fiyero and Elphaba, with Glinda essentially a supporting character. The finished story instead focused on the RomanticTwoGirlFriendship, making Fiyero more of a SatelliteLoveInterest.

[[/folder]]

[[folder: Video Games ]]

* ''VideoGame/{{Halo|Combat Evolved}}'' was originally conceived as a RealTimeStrategy game, but it made it to shelves as a FirstPersonShooter, probably because its plot and factions coupled with its genre would have made it too similar to RTS heavyweight ''{{Starcraft}}''. [[VideoGame/HaloWars They eventually revisited the RTS idea, though]].
** Also, the developers changed genres because they decided they wanted to play as the soldiers. Initially ''Halo'' was a third person shooter for Macs (which can be seen in early videos and screenshots) but became a first person shooter when Bungie was purchased by Microsoft.
* A light variation with ''SonicTheHedgehog'', the initial concept was a more traditional platformer with puzzles and exploration akin to ''VideoGame/SuperMarioBros2''. The final product, while still a platformer, focused more dominantly on its now trademark speed. This evolution is even more prominent in [[VideoGame/SonicTheHedgehog2 its sequel]].
* According to [[http://www.1up.com/news/super-mario-bros-25th-miyamoto 1up]][[note]]translated from an interview in Famitsu[[/note]], the NES version of ''SuperMarioBros'' was going to be a shoot-em-up platformer, and Mario was going to carry guns, [[http://iwataasks.nintendo.com/interviews/#/wii/mario25th/4/0 like the beam gun]] similar to those in ''{{Metroid}}'' and a rifle. [[HilariousInHindsight Also, he was going to]] [[VideoGame/SuperMario64 punch and kick enemies while empty-handed]], [[VideoGame/SuperMarioWorld ride on clouds]] (which were previously {{r|idingTheBomb}}ockets in earlier development) and fire at enemies in cloud drive-bys that would soon become [[BonusStage bonus coin stages]]. Also, the "jump button" was going to be "up" on the Control Pad, leaving the "A" button open for attacks.
* {{Rareware}} has a habit of doing this:
** ''VideoGame/BanjoKazooie'' was originally conceived as ''Dream'', a 2D SuperNintendo RPG with human characters rather than a 3D FunnyAnimal platformer.
** ''VideoGame/GoldenEye1997'' was originally to be an on-rails light-gun shooter like ''VideoGame/LethalEnforcers'' or ''VideoGame/VirtuaCop''. Before that it would have been a pre-rendered 2D platformer, like ''VideoGame/DonkeyKongCountry'' but with guns. The unrelated GameBoy James Bond game is much closer to this design.
** ''VideoGame/ConkersBadFurDay'' was originally just another generic kiddie platformer before they retooled it into the rude, crude, offensively over-the-top game everyone knows and loves. This was ''after'' the tie-in Game Boy game, which really was as saccharine as Conker was intended to be, had been released as well.
** ''VideoGame/StarFoxAdventures'' started off as an original IP titled ''Dinosaur Planet'' before ExecutiveMeddling told them to retool it into a ''Star Fox'' game, complete with {{shmup}} sections and [[HijackedByGanon a surprise final boss]] that were so very obviously tacked-on near the end of production.
* ''[[VideoGame/RavingRabbids Rayman Raving Rabbids]]'' was conceived as a Rayman 2-esque platformer with original creator Michel Ancel having full involvement, but ExecutiveMeddling caused the switch to a minigame collection and Ancel being dropped from the project.
* ''VideoGame/MetalGear'' began development as a straightforward shoot-'em-up, cashing in on the popularity of Capcom's arcade game ''Commando'', but the programmers were having too much trouble creating a similar game on the [=MSX2=] since the hardware couldn't handle too many enemy soldiers and bullets on-screen at the same time. When HideoKojima was brought into the project to salvage it, he decided to shift the game's focus to avoiding combat.
** ''VideoGame/MetalGearSolidPortableOps'' started development as an online multiplayer deathmatch-style shooter unrelated to the main ''Metal Gear Solid'' storyline. ''Portable Ops Plus'' does include the online multiplayer though.
** ''VideoGame/MetalGearRisingRevengeance'' originally was named ''Metal Gear Solid: Rising'' and was a stealth-action game that emphasized hunting enemies. When the game switched developers from Kojima Productions to Creator/PlatinumGames, the stealth aspect was toned down in favor of more straightforward combat (hence the title change), though some stealth remains as the player can kill enemies without them expecting it.
* ''{{Shinobi}}'' began development as a game about shooting shurikens at enemies from a first-person view. The developers planned to include a shuriken-shaped paddle to control the player's aim. The concept didn't prove to be that interesting and Sega decided to revamp ''Shinobi'' as a side-scrolling action game, with the shuriken-throwing game idea used for the bonus stages instead.
* ''VideoGame/{{Thief}}'' started life as an Arthurian legend swashbuckling game with minor emphasis on stealth with the tentative name ''Dark Camelot''. Once Looking Glass Studios realized just how ''good'' they made stealthing (ie, enemies not able to see you in the dark and having to be aware of your footsteps), they made a game specifically tailored for the mechanic, instead.
* The ''Videogame/RobinHoodPrinceOfThieves'' game for the NES by Sculptured Software was initially conceived as an action RPG titled ''The Legend of Robin Hood'' which originally [[DolledUpInstallment had nothing to do with the movie]]. After tacking on the movie license, the game's publisher, Virgin Interactive, [[ExecutiveMeddling forced the developers to make it into a more straightforward action game.]]
* ''VideoGame/TabulaRasa'' was developed as a fantasy MMORPG before becoming a sci-fi MMOFPS.
* ''VideoGame/TeamFortress2'' began as a realistic, serious FPS that was going to be just like [[VideoGame/TeamFortressClassic its predecessor]], but with more realistic physics. Then in 2003, they retooled it into a sci-fi FPS entitled ''Invasion'', which involved a humans vs. aliens plot. Finally, in 2006, the game was retooled into the humorous, cartoonish, lighthearted FPS we all know of today.
* ''Franchise/FinalFantasy'':
** ''VideoGame/FinalFantasyVII'':
*** The game's plot was originally conceived as having a real-world American UrbanFantasy [[NoirEpisode Noir]] setting inspired by popular mid-90s TV shows like ''Series/TheXFiles'' and ''Series/TwinPeaks'', which would focus on a HotBlooded detective tracking down a group of terrorists in the mean streets of New York. At some point it was decided to make it into a more conventional HighFantasy setting, although still featuring [[TheBigRottenApple The Big Rotten Pizza]] and a quasi-'murder mystery' ("who killed Sephiroth?") in a disturbing mountain town.
*** As a hangover from the above concept, Vincent was intended to be a GenreRefugee from 90s American television, an {{Expy}} of [[Series/TheXFiles Agent Mulder]] and [[Series/TwinPeaks Agent Cooper]], being a secret agent, conspiracy theorist, movie fanatic and amateur occultist who stumbled upon the goings-on in [[TownWithADarkSecret Nibelheim]] and was transformed into a shapeshifter. Relatively late in development he was retooled into a more straightforward GothicHorror-themed character without the AscendedFanboy elements, and his backstory revised to fit more into the main storyline.
** ''VideoGame/FinalFantasyX'' started as a non-''FF'' project called "Seventeen", which would have been a sci-fi game about a virus that killed people on their eighteenth birthday, and a seventeen-year-old doctor/priestess who was travelling all over the world to deliver vaccines on behalf of a pharma company/cult. Later, it would have become apparent that the cure was actually causing the sickness, and this was deliberately engineered by the pharma company to establish social control. When it was decided to make it into a ''Final Fantasy'' game instead, the setting was reformatted into a fantasy world besieged by a monster, while the doctor became a religious pilgrim ready to give her life to temporarily destroy the monster in a ritual used by a CorruptChurch to maintain theocratic control.
[[/folder]]

[[folder: Western Animation ]]

* ''WesternAnimation/TheDreamstone'' was initially conceived as DarkerAndEdgier storybook with more action and mystical concepts. While some of these concepts make it into the final TV series (the pilot episode, especially), the setup was reinvented into a more light-hearted RoadRunnerVsCoyote style cartoon.
* ''WesternAnimation/PlanetSheen'' was intended to be more serious and dramatic, but it ended up becoming even DenserAndWackier then ''JimmyNeutron''
[[/folder]]
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