When something goes from one medium to another, it's because of two elements:
# It's popular!
# [[MoneyDearBoy Producers like money!]]

Moving something to a new medium is a way of breathing new life into an existing product which generates two things. New revenue from the fans, and new revenue from potential fans who for one reason or another never were into it in its original medium, but might get into it here.

This is where the problem arises. Take for instance a comic book being turned into a movie. Most comics have up to 70 years of {{backstory}}, cool sequences, and ranging from a handful to an army of cool heroes and villains. All that has to be crammed into a two-hour presentation or the longtime, diehard fans are upset. Meanwhile, it has to be perfectly understandable, and -- more importantly -- easy to follow, [[ContinuityLockout or else the new blood won't like it]].

Ultimately this leads to a dangerous balancing act, one that is rarely done right, although producers appear to be getting better at it. You need to throw in enough of the classics and not change things too much or you alienate the fanbase, but at the same time you can't rely on in-jokes or backstory or you'll lose the new blood. While the fanbase may be more loyal, the new blood represents more money for the new genre, so as far as the scale goes it almost always tips to the new blood side.

Before continuing, it's important to understand two things. First of all, any examples here are at best subjective. For this reason, an example could show up in more than one location under different arguments. This is allowed. Everything has an implied "arguably" in front of it.

Secondly, an example being in any of the three categories does not necessarily indicate that it's bad. A movie that has nothing to do with the original premise can still be enjoyable, as can one that is very hard for newcomers to follow.

One common way to balance the scales is to adapt the characters and styles, while only representing the original ''story'' in broad strokes, sometimes only keeping parts of the origin story. Most ComicBook movies produced around the 2010s follow this method.

See also: InNameOnly for the more extreme New Blood cases, or TheyChangedItNowItSucks and PanderingToTheBase for the more extreme Old Guard cases. Also see NewbieBoom and ItsPopularNowItSucks.
* ''Franchise/TheHitchhikersGuideToTheGalaxy'' has been in ''every'' major media type in the world. It started on [[Radio/TheHitchhikersGuideToTheGalaxy the radio]], then it was [[Literature/TheHitchhikersGuideToTheGalaxy a series of novels]], then [[Series/TheHitchhikersGuideToTheGalaxy a TV show]], [[VideoGame/TheHitchhikersGuideToTheGalaxy a text-based adventure game]], [[Film/TheHitchhikersGuideToTheGalaxy a movie]], a stage play, a comic book, a towel, it's been released on LP, CD, and cassette. About the only thing there isn't is a ''Hitchhiker'''s ballet. But every single re-release is different from ''all'' the others. Invariably, of course, people start to complain about the things that were added and the things that were left out, with nobody being able to say which is the definitive version or which version is pandering to whom.
** You can be certain that Creator/DouglasAdams himself found that fact very funny.
*** "The book is, as the title suggests, a collection of all the radio scripts, as broadcast, and it is therefore the only example of one Hitchhiker publication accurately and consistently reflecting another. I feel a little uncomfortable with this -- which is why the introduction to that book was written after the final and definitive one you are now reading and, of course, flatly contradicts it." --Douglas Adams, The Ultimate Hitchhiker's Guide, Introduction, referring to a recently published book of the complete scripts of the radio version
*** This got to the point where, when asked exactly how much material was going into the film version--would it be closer to the radio series or the books? Would it collect the whole story or just the first installment?--Adams answered that the film would "directly contradict only the first book."

!!Examples that tip towards New Blood:
* ''Film/DungeonsAndDragons'' the movie: Suffered severely from conflicting ideas that they wanted to attract the ''Dungeons and Dragons'' fanbase and at the same time alienate themselves from them for fear of being associated with "losers." As a result the movie was written by somebody who had never played the game, and the movie has lip service to the game and nothing else. A token, 5'4" dwarf, clerical magic being only accessible to elves, and Beholders that don't take advantage of the fact that they can look in all directions at once are just a few of the conflicts.
* ''Film/{{Underdog}}:'' Instead of being about a shoe-shine boy in a city of anthropomorphs, it's about a pet talking dog with Green Rocks.
* The ''Film/SuperMarioBros'' movie: It had plumbers, mushrooms (sorta), and a dinosaur, but other than that had [[InNameOnly nothing to do]] with [[Franchise/SuperMarioBros the games]]. The bob-omb was its selling point.
* ''VideoGame/DoubleDragon:'' Both the [[WesternAnimation/DoubleDragon cartoon]] and the [[Film/DoubleDragon movie]] took the Double Dragon legends in different directions. The movie made it a post-apocalyptic gang-war for a mystical medallion, whereas the cartoon turned Billy and Jimmy into ninja super heroes. Both were entertaining, but had little to do with the video games.
** The comic mini-series (released by Marvel) split the difference; making Billy and Jimmy twin super-hero ninjas powered by a mystical statue. It also featured a SoBadItsGood extended cameo by [[spoiler:Creator/StanLee as Billy and Jimmy's biological father.]]
* ''Night of Dark Shadows'' came out in 1971 and, while ''Series/DarkShadows'', the television series it was based on, had only recently gone off the air, the plot and characters bore little or no resemblance to anything on the show.
* ''Series/DoctorWho'':
** The TVMovie, which had been intended to start a ReBoot series but flopped, altered the formula to resemble then-trendy series ''Series/TheXFiles'', gave a drastic SameCharacterButDifferent retool to the Master, altered the Doctor's backstory and (if it had been made) would have focused on remaking popular Classic stories like "Pyramids of Mars" and "The Robots of Death". The BBC had even wanted to toss out the current incumbent Doctor, Creator/SylvesterMcCoy, in favour of having the more popular and recogniseable Creator/TomBaker regenerating into Creator/PaulMcGann, before FOX persuaded them not to. And yet the main criticism of the movie (apart from anger about all the kissing) is still ContinuityLockOut.
** When Creator/RussellTDavies soft-rebooted the series he realised he could only do so if he did not cater to FanWank and aimed the show at the mainstream, as ''Doctor Who'' had been a mainstream show in its heyday in the UK and was only regarded as a cult show in the US and during its DorkAge. Doing this required him to reboot it in the form of a GenreBusting drama, incorporating elements of SoapOpera, [[ThrowAwayCountry killing off the Time Lords]] [[ThePlotReaper to simplify things]] and provide opportunity for {{Mangst}}, and deliberately avoiding bringing up most of the show's continuity in the first season in favour of spending five episodes dripfeeding information about basic concepts like "who and what is the Doctor?" and "are those big metal pepperpots with plungers on them bad news?". There wasn't an unambiguous suggestion the revival even happened in the same continuity as the Classic series until the return of Sarah Jane and K-9 in Series 2, and the show avoids the issue of the Doctor's [[TheNthDoctor former selves]] until some drawings in a journal in Series 3, only giving it a [[IntroDump significant scene]] in Series 4 when the show was leading up to the Doctor's regeneration and needed to remind audiences that Tennant had not always been the Doctor. The monsters are largely new, with only the iconic Daleks, Cybermen and the Master, and the popular Sontarans, Silurians and Macra returning. While many elements of the UnpleasableFanbase felt this occasionally turned the series into ''Doctor Who'' InNameOnly, the series was successfully brought back on television in a popular and highly regarded form, despite being remembered as a cheesy {{Camp}}y relic from TheSeventies with lots of SpecialEffectsFailure up until that point. After RTD left, Creator/StevenMoffat's tenure as showrunner shifted the show back towards the Old Guard side of the spectrum by dropping a lot of the soap elements, adding plot-important references to the Classic Doctors and reviving old-school story formats like GothicHorror and [[TheSiege Base Under Siege]] - but also remained focused on grabbing new fans by [[SoLastSeason discarding all of the Russell T Davies-era continuity that didn't directly affect the Doctor]], and only revived three Classic monsters that hadn't already been reintroduced to the series (Zygons, the Ice Warriors and the Great Intelligence).
* ''Franchise/PowerRangers'' has a surprisingly large PeripheryDemographic of older fans who started watching the show when in began in 1993 and still do for the nostalgia it gives them. The powers that be have acknowledged this and started slipping in older references that the under-12 set simply won't get (the pilot episode of ''Series/PowerRangersMegaforce'' was almost [[Series/MightyMorphinPowerRangers "Day of the Dumpster"]] all over again). However, they also have said that, while they appreciate the older fans, they have to realize that the target demographic (and biggest [[MerchandiseDriven toy-buying market]]) are still young children, and that's something they simply have to deal with. For the most part, older fans are fine with this (as it's [[NarmCharm the show's campiness]] that they enjoy); they only really get upset if the Powers That Be use the fact that the show is 1) MerchandiseDriven and 2) For Kids as an excuse to be lazy and do the show badly.
* ''VideoGame/{{Fallout 3}}'' was deliberately set far away from anything related to the first two installments to allow a new team the freedom to operate without necessarily being bound by canon. This, combined with the jump to real-time and a first-person/over the shoulder view like ''Franchise/TheElderScrolls'', completely alienated much of the existing fanbase. Bethesda realized that they weren't going to get that set of the fans on board and didn't worry about it too much, playing to their strengths and going with the basic theme of a somewhat-farcical post-nuclear setting based on an exaggeration of TheFifties, while taking a few set-pieces like the Brotherhood of Steel, ghouls and super-mutants and using them as they chose. The game is immensely divisive in the ''VideoGame/{{Fallout}}'' fandom, but made exactly the profits you'd expect from a AAA title by Bethesda.

!!Examples of balanced scales:
* 2007's ''Film/{{Transformers}}'' LiveActionAdaptation: Majorly re-wrote the storyline, bringing the US military in and making it easier to follow, while giving enough in-jokes and old quotes to keep the old fans happy. And Peter Cullen to pack them in the aisles in the first place.
** And then there's ''WesternAnimation/TransformersAnimated'', which brought a new art style to the cartoon and placeed more emphasis on human supervillains to keep the Decepticons from looking ineffective, but won over a lot of converts in short order via strong writing and good use of the MythologyGag.
* ''ComicBook/VForVendetta'' probably stands about in the middle here. It updated the political context and generally made it a bit more [[Film/VForVendetta film-y]] (stronger female protagonist, more action scenes, less moral ambiguity), while keeping a lot of dialogue, visuals and themes from the comic. On the other hand, the changes to the politics and moral ambiguity made it essentially a completely different story, leading to the creator disowning it.
* Later Music/{{Radiohead}} albums have been trying to strike this sort of balance; ''In Rainbows'' successfully, ''Hail to the Thief'' perhaps less so.
* ''WesternAnimation/XMenEvolution'' brought in a new art style and a completely new set of storylines while keeping as many old characters as they could. Their main new character, Spyke, failed testing and [[PutOnABus was written out]] (and a version of him was even executed by Wolverine in the unrelated ''X3'' in a cool, but one-sided fight). ComicBook/{{X 23}}, on the other side, became popular enough with only two episodes worth of screening to be ported into the comics.
** The original animated series also balanced quite well, even keeping some of the original storylines and adapting them to the format of the show.
* Similarly, Marvel's [[ComicBook/UltimateMarvel Ultimate series]] is an attempt to bring casual and new fans into the fold by recreating their most popular works (Comicbook/SpiderMan, Comicbook/XMen, ComicBook/FantasticFour, and ''Comicbook/TheAvengers'') from the ground up. Although almost all villains and heroes are extremely familiar, they've all received major make-overs and have had their [[BackStory backstories]] {{retool}}ed and modernized. In one of their most controversial points, they've removed Peter Parker's job as a photojournalist and made him a webjockey instead.
* The writers of the new ''Series/DoctorWho'' are walking this tightrope very well, especially when you consider that they have a damn near UnpleasableFanbase sometimes.
* ''Film/{{Serenity}}'' tried to present a self-contained story, and enough back history on the ''Series/{{Firefly}}'' [[TheVerse verse]] to be accessible to newbies, with enough nods to the series to please the hardcores. Ultimately, though, the amount of people that even knew what Firefly was, much less get interested enough to go see it, [[SmallReferencePools was just a little bit low]].
* The ''ComicBook/IronMan'' [[Film/IronMan movie]] is another strong example of this process done successfully.
* Fanboys and regular moviegoers alike sure seem to enjoy ''Film/TheDarkKnightSaga''. Note that regular folks reacted to ''Film/BatmanBegins'' being made with "Batman? With the rubber nipples and terrible, campy villains? Why are you going back to that again?" and fanboys reacted to Creator/HeathLedger being cast as SelfDemonstrating/TheJoker in ''Film/TheDarkKnight'' with "That Film/{{Brokeback|Mountain}} prettyboy as the Joker? This is gonna SUCK!". Note further that both sides have since been forced to eat their own words in dramatic fashion.
* The ''Franchise/MortalKombat'' [[Film/MortalKombat movie]] was enjoyed by the fans for being a faithful adaptation and moviegoers and critics enjoyed it for being a coherent action movie.
* The ''WesternAnimation/SouthPark'' movie makes sense if one hasn't seen the show, while still serving as a good episode of it.
* The Creator/JJAbrams ''Film/StarTrek'' films seem, to a neutral outside observer, to be pretty balanced - perfectly comprehensible to a newbie, with enough {{Shout Out}}s to the Prime 'verse to satisfy even the most die-hard Trekkie. Indeed, the films were praised by critics and loved by fans new and old alike. Within the fandom itself, it is [[BrokenBase either]] a wonderful and necessary revitalization of the franchise or a travesty that has ruined Trek forever and brought a legion of godawful [[FanDumb newbies]] down upon the heads of "real fans." [[InternetBackdraft Bad things happen when the opinions mix]].
* ''TabletopGame/MagicTheGathering'', as of late. The power-creep has been pretty damn noticeable lately, which makes older players cringe, and the newer ''Franchise/YuGiOh''-influenced generation squeal; however, the bar-none best cards are still those from well over 10 years ago, and the costs of these cards, whether the originals or in special reprint sets & decks, can easily run 40 bucks for a playset (4), making "veteran" formats like Legacy a nightmare for newer players to compete in. Let's just say that Magic is "balanced" in that [[UnpleasableFanbase it manages to delight and piss off both sides equally]].
* ''House of Dark Shadows'', the 1970 film based on the cult hit soap opera ''Series/DarkShadows''. It was not only filmed and released while the series was still on the air, but actually retold one of the show's early story arcs, albeit with a "new" (though WordOfGod says this was the original plan) twist on the ending of said arc.
* ''VideoGame/FalloutNewVegas'' was intentionally made to bridge the gap between the ''Fallout'' old guard and new blood, starting by bringing in [[Creator/ObsidianEntertainment one of the successor studios of the series' creator Black Isle]] to do the game back on the West Coast, but doing it with the updated engine and SPECIAL system from ''3'' and continuing to innovate in storytelling and setting lore. The result was a game that both old-school ''VideoGame/{{Fallout 2}}'' purists and ''VideoGame/{{Fallout 3}}'' fans agree is an excellent entry in the series.
* ''WesternAnimation/MyLittlePonyTheMovie2017'' requires no prior knowledge of the [[WesternAnimation/MyLittlePonyFriendshipIsMagic cartoon it's based on]], nor does it require being a Brony to fully appreciate; however, it still has plenty of bonuses for the former two.

!!Examples of falling on the Old Guard side.
* ''[[Film/TheFlintstones Flintstones]]'' the movie: Almost the entire movie is focusing on the comedy of turning the old visual gags into live action, while following a stretched-out ''Flintstones'' plot. And the [[CanonDiscontinuity less said]] about the ''second'' movie, the better. What makes it especially old guard are the adult subplots and ParentalBonus material, such as Fred being seduced by a woman who knew he was married. This kind of thing was common with cynical 90's updates of movies and series from more "innocent" decades. As if people were unaware of the missing themes just because those themes weren't present in movies and television.
* ''WesternAnimation/TheSimpsonsMovie:'' Granted, the Simpsons' fan base is so large that they could get away with this entirely. Still it was packed with so many in-jokes that even long term fans were forgetting a lot of them. Of course, the first thing the movie did was draw attention to the fact that it is virtually a giant Simpsons episode, so they probably knew that.
** It is the same case for ''VideoGame/TheSimpsonsGame''.
* ''Film/SinCity:'' Whether it works for it or against it is up to debate, but the movie religiously follows the comics (except when it comes to displaying nudity), to the point where the comics are literally used as storyboards.
* ''StarWars'' [[Franchise/StarWarsExpandedUniverse novels]] are technically this; having mostly created the old guard in the first place, they continue to cater to them. Some of the later books however are being written with the concept of drawing more people in, and are avoiding making too much reference to the older books.
* ''Film/SupermanReturns'', a film that by all rights, ''should'' have been a reboot of the franchise that ended up becoming a sequel to a movie that came out [[Film/SupermanII close to 30 years previously.]] Bryan Singer turned the movie into his own personal love letter to the Christopher Reeve movies. Critics and audiences who grew up with the original films showered it with praise while [[CriticalDissonance new audiences were completely frozen out.]] The movie ultimately ended up disappointing at the box office.
* ''Film/{{Watchmen}}'' is in the same situation as ''Sin City'', except instead they had to cut and compress more content for time (some re-instated in DVD), didn't keep the visual style (although keeping most of the framing intact), and deciding this time to ''keep'' the male nudity.