When two or more works, be they books, movies or comics or two completely different media altogether, exist in SharedUniverse or ExpandedUniverse, you are expecting them to be bound to the rules that come with this fact - when something big, involving all known worlds happens, you are expecting this event to be referred to in several titles. For example, when somebody dies in one work, he wouldn't appear in another, and internal rules like [[MagicAIsMagicA magic]] apply no matter which work you are reading, watching, playing, or listening to.

Well, this isn't always the case. Maybe the writer decided that CanonWelding was a bad idea in retrospect. Or they didn't want to feel limited by what happened in another title. As well as the possibility of the writer wanting to take the works in a different direction, or that the writer was afraid being too continuity-heavy would discourage assorted potential readers. Whatever the reason may have been, the writer doesn't really act like the titles currently are in one continuity.

In order to avoid [[ContinuitySnarl several]] [[ArmedWithCanon kinds]] [[CanonDiscontinuity of]] [[FanonDiscontinuity problems]] that could come from not sticking to one continuity, some writers may decide to announce that two or more works are still in continuity ''and'' are not, from a certain point of view.

There are a few varieties of this trope:
* '''One-Sided Continuity''': ''Work A is in continuity with Work B, but Work B is not in continuity with Work A.'' So works from one title are still canonical and its characters may show up in the other, but not the opposite. It might be explained that characters from Work A exist in their own, separated world, and Work B is an AlternateUniverse, where their counterparts exist, but their adventures may go different ways and they may meet characters that may not even exist in the title they originate from.
** '''AlternateTimeline Continuity:''' ''Work A was always in AlternateContinuity for Work B, but the timelines were identical until a certain point, at which point they diverged.'' Sub-Variant of One-Sided Continuity, chances are, this will be used either when two or more titles start going in two or more different ways, or in case at least one of them is set in a different time from others. Going from this, it would be that one or more of the works happening later on the timeline are a possible future and things don't have to turn out like they did in it.
* '''Bait-And-Switch Continuity''': ''Work A and Work B don't take place in one continuity, unless said otherwise''. In other words, two titles have their own, separate settings, but whenever the writer wants to, they can meet and the crossover in question will act as if and were always set in one continuity. CanonWelding is however averted, because once the {{Crossover}} is over, assorted characters [[CanonDiscontinuity act like it never happened]]. Needless to say, this is can be extremely jarring for more continuity interested fans, who wouldn't accept that and will try to explain how two titles can exist in one world, even if several works aside from crossovers contradicts that.
* '''Divorced Continuity:''' ''Work A and Work B existed in the same world, but something split it in two.'' This variant is similar to AlternateTimeline, but there was an event in-universe that had resulted in separating two worlds - all the history from one work has been removed from the history of another and vice versa, [[RetGone the characters never existed in one world and nobody remembers them]] as their stories exist [[OrwellianRetcon and always existed]] separately. Alternatively, in order to avoid creating ContinuitySnarl, [[{{Expy}} Expies]] are created to fill the roles of deleted characters.

Compare and contrast CanonDiscontinuity, AlternateTimeline and TheMultiverse, ExiledFromContinuity and CanonWelding

!Examples of One-Sided Continuity:

* This type of continuity is extremely common for tie-ins of major television series or films (and to a lesser extent, other media like video games or cartoons). Spinoffs or followups to the main series almost never get referenced in the main series despite supposedly being set in the same universe. For example, all the television shows, comics, and licensed video games stated to be set in the Franchise/MarvelCinematicUniverse never get explicitly mentioned in any of the films, with a few implied nods at best. This could be considered an EnforcedTrope for the simple reason that it would get confusing for the audience if they needed to scour through three or four different media to understand the plot of just one.
* The ''Franchise/MyLittlePony'' G4 cartoons, ''[[WesternAnimation/MyLittlePonyFriendshipIsMagic Friendship Is Magic]]'' and ''[[WesternAnimation/MyLittlePonyEquestriaGirls Equestria Girls]]''. They share the same characters and the same writing staff, and these writers have insisted that the events of ''Equestria Girls'' actually are canon to ''Friendship Is Magic''. But the character arc in ''EQG'' is completely dependent on a big event from ''FIM'' season three, while ''FIM'''s only reference to ''EQG'' have been a few blink-and-you'll-miss-it cameos. So even though ''EQG'' is technically canon, it's totally ignorable [[FanonDiscontinuity for the fans who are so inclined]].
** This also extends to the [[ComicBook/MyLittlePonyFriendshipIsMagicIDW comics]]. The events of the cartoon have happened, mostly, but the comics have yet to be referenced in the cartoon, with a few episodes strongly implying that the comic stories haven't happened, and members of the staff have said the comics won't affect or be referenced in the show.
* [[ComicBook/DisneyMouseAndDuckComics Disney comics]] in general — BroadStrokes versions of most of the [[Franchise/DisneyAnimatedCanon Walt Disney Classics]] exist within the comic universe[[note]] Creator/DonRosa's personal views on continuity notwithstanding, of course, since he's a whole other problem.[[/note]], but don't expect to see any anthropomorphic characters in sequels and merchandise for these.
* ''Franchise/StarWars'' and its ExpandedUniverse had this relationship under Creator/GeorgeLucas: the movies and ''WesternAnimation/StarWarsTheCloneWars'' were in canon with all books, comics and games, but Lucas refused to acknowledge the opposite and contradicted them on a regular basis (a big one being that most works written prior to the prequel trilogy assumed that the Clone Wars and the Jedi Purge had been two separate conflicts that took place about twenty years apart, causing any number of {{Continuity Snarl}}s). In 2014, new owners Creator/{{Disney}} roped off all previous material other than the then-six films and ''The Clone Wars'' as ''Franchise/StarWarsLegends'', and declared that all subsequent Franchise/StarWarsExpandedUniverse material would be considered official canon, though contradictions have inevitably crept in anyway over time due to the sheer amount of material.
* Ditto for ''Franchise/StarTrek.'' The TV series and movies are considered canon by the novels and comics, but not vice versa. Unlike the ''Star Wars'' ExpandedUniverse, however, ''Trek's'' various comic series and individual novels were not considered in canon with ''one another,'' until ''Star Wars'' popularized the idea in the 2000's and ''Trek'' followed suit with its novels. [[note]] [[Creator/GoldKeyComics Gold Key]], [[Creator/MarvelComics Marvel]], [[Creator/DCComics DC]], Creator/TokyoPop, [[Creator/IDWPublishing IDW]], and even a short-lived [[NewspaperComics newspaper strip]] have all published ''Star Trek'' comics over the years, and none of them are in canon with one another. [[/note]]
* Involving the Franchise/MarvelCinematicUniverse:
** The connection with Film/SonysSpiderManUniverse has always been messy, as Sony owns the rights to ComicBook/SpiderMan characters, but made the MCU films ''Film/SpiderManHomecoming'' and ''Film/SpiderManFarFromHome'' in conjunction with Marvel Studios.
*** While Marvel has specifically stated that ''Film/Venom2018'', starring a [[Comicbook/{{Venom}} popular Spider-Man opponent]], is not in continuity with their shared universe, Sony has made comments implying that they are. (Or at least, in continuity with ''Homecoming'', which is too connected to other MCU films to easily write them off.)
*** The third MCU film, ''Film/SpiderManNoWayHome'', finally solidified that the MCU and SSU are separate continuities, but that they are connected with each other (along with the ''Film/SpiderManTrilogy'' and ''Film/TheAmazingSpiderManSeries'') as different universes in a shared multiverse. They would later reinforce this with yet another film series, ''WesternAnimation/SpiderManSpiderVerse'', which connects several ''Spider-Man'' continuities including all four film series (five including itself).
*** Even with ''No Way Home'' establishing the multiverse, there are still one-sided aspects with Sony making references to the MCU in both the SSU and ''Spider-Verse'' that aren't reciprocated. TheStinger of ''Film/Morbius2022'' even has [[spoiler:the Vulture {{Transplant}}ed from the MCU to the SSU]], something that the Marvel films are unlikely to ever acknowledge.
** ''Series/AgentsOfSHIELD'' became an example of the Alternate Timeline as of its last seasons. Seasons One through Five kept right in line with the MCU right up to ''Film/AvengersInfinityWar'', with the final episodes explicitly taking place during Thanos' attack in that film. But then the show received a surprise renewal for two more seasons and could not account for the end of ''Infinity War'' and ''Film/AvengersEndgame'' (either the staff was not appraised of what was happening in the films, or could not risk the possibility of spoiling ''Endgame''). As a result, the major shift to the status quo at the end of ''Infinity War'' just... never happened; and the staff claimed that the final seasons were being retconned into occurring before ''Infinity War'' (despite the fact that Season Five specifically referenced the events of the film, and that the later seasons included a couple years of {{Time Skip}}s). This isn't as problematic as it could be, however, given that both the movies and ''Agents of S.H.I.E.L.D.'' have featured the concept of the Quantum Realm connecting alternate timelines. Season 5 of ''Agents of S.H.I.E.L.D.'' opened with the team taking a trip to a BadFuture, so according to the established rules of the MCU multiverse, everything after Season 4 could take place in an alternate continuity.
** In a rare example of one-sided continuity where the ''original'' media is the one that maintains it, Creator/MarvelComics considers all Marvel media to be part of the same Multiverse, with the MCU being Earth-1999999. The MCU disagrees, numbering the Sacred Timeline as Earth-616 of its own multiverse, introducing their own version of the Time Variance Authority (who are supposed to be pan-universal) in ''Series/{{Loki|2021}}'', and claiming that their Comicbook/AmericaChavez has ''no'' [[AlternateSelf Alternate Selves]] in ''Film/DoctorStrangeInTheMultiverseOfMadness''. (And just to complicate the MCU's relationship with Sony's films, ''WesternAnimation/SpiderManSpiderVerse'' takes the comics' side and uses their ID numbers.)
* ''Film/BatmanFilmSeries'': In the Arrowverse Crisis on Infinite Earths behind the scenes feature, ''After Crisis'' WordOfGod affirmed that ''Film/Batman1989'' and ''Film/BatmanReturns'' take place on Earth-89 while ''Film/BatmanForever'' and ''Film/BatmanAndRobin'' take place on Earth-97, however, by the way it was said it is implied that it was just a joke about the films release dates plus the own films seems to imply otherwise: In ''Film/BatmanForever'' Chase Meridian asked Batman if she needed "[[ComicBook/{{Catwoman}} skin-tight vinyl and a whip]]" to get his attention, suggesting that at least the events of the first two movies happened on the hypothetical Earth-97, but the events of the second two did not happen on Earth-89. However, ''ComicBook/Batman89'' rolls with it an presents a version of Two Face incompatible with the 3rd film but compatible with Harvey Dent's brief cameo in Batman(1989). However, comic book solicitations for Dark Crisis imply that the Batman '89 universe is making an appearance in the event. In the actual event Main!Batman from the comics travels across the DC Megaverse to the Live-Action DC Multiverse were he encounters Movie!Batman and they make a ContinuityNod to the Arrowverse depiction of Earth-89. Another comic that includes a map of the multiverse by Comic!BarryAllen suggest that instead the Batman '89 and Superman '78 series of comic books both take place in an Earth called 'Earth-789. Film/The Flash again presents a version of Earth-89 as the Flashpoint timeline of the DCEU, however since the DCEU was established as being part of the same Live Action Multiverse as the Arrowverse and the movie shows a cameo of the Earth's of the multiverse colliding is implied rather strongly that the 'Flashpoint Earth-89' is a temporal merge of the DCEU and the real 'Earth-89' (Still only the 2 first films get referenced, except in the final Post-Flashpoint scene, were is implied Earth-97 fused this time with the DCEU). So at the end it doesn't matter if you are in Earth 89, 97, 789 or the DCEU, or if you are in the comic or live action multiverse the only firmly canon movies are always the first two.
* ''Webcomic/{{Acrobat}}'' had been a part of ''Webcomic/HeroesUnite'' until the former's creator announced that his characters appearing in latter and related titles are not the originals, but their alternate counterparts.
* ''Webcomic/SugarBits'' and ''Webcomic/{{Everafter}}'' had a crossover within the pages of the former, but Creator/{{Bleedman}} has let the latter's creator decide if he wants them to share TheVerse. It's hard to ignore all pages with Red [[spoiler: and Big Bad Wolf]] in ''Sugar Bits'', so it's safe to say that ''Everafter'' exists in the ''Sugar Bits'' world, but the opposite may be not true.
* ''Webcomic/{{Mindmistress}}'' and ''Webcomic/ZebraGirl'' were established as existing in one Universe, but WordOfGod from the creator of Mindmistress is that the Zebra Girl from her world may not be the original one, but an alternate version.
* In similar manner, two webcomics that established a large [[TheMultiverse Multiverse]] do it: ''Webcomic/TheCrossoverlord'' and ''Webcomic/{{Crossoverkill}}'' both portray ''Webcomic/TheOrderOfTheStick'' as existing in that multiverse, but WordOfGod says that unless Rich Burlew will agree with that, it's only "one of many worlds working on similar rules and laws physics as ''The Order of the Stick''". In general, CanonWelding done by the two series may result in this if creators of comics dragged into TheMultiverse don't want them to.
* WordOfGod states that ''VideoGame/TheWitcher'' games are just one possible future for ''Literature/TheWitcher'' book series. This is in case Sapkowski would want to write a sequel to the series, and so he wouldn't have to reference the games.
* WordOfGod has said that the ''Series/ResidentEvil2022'' series is not canon to the games; however, the games (up to ''[[VideoGame/ResidentEvil5 5]]'') are canon to the series. The BroadStrokes used to paint the lore and background meant there were many inconsistencies between the series and the games that were canon to it. This has led to the conclusion that the series is better labelled as ''Resident Evil'' InNameOnly.
* The ''TabletopGame/DiscworldRoleplayingGame'' outright states (in the sidebar "Officially Unofficial") that it is written to at least not contradict anything in the ''Literature/{{Discworld}}'' novels, but the books were under no compunction to be in continuity with the game. (The second edition had to tweak a few things based on later novels, most notably that the adventure "Full Court Press" made some assumptions about how refuse collection in Ankh-Morpork worked that were completely contradicted by the introduction of Harry King.)
* ''Series/MadAboutYou'' revealed that Paul sublet his old apartment to Kramer from ''Series/{{Seinfeld}}'', and that Jerry lived in his apartment before Kramer moved into his. On ''Series/{{Seinfeld}}'' George and Susan are seen watching ''Series/MadAboutYou'' on T.V. and it was established that Kramer lived in his apartment before Jerry moved into his.

!Examples of AlternateTimeline Continuity:
* The second-edition ''TabletopGame/TrinityUniverseWhiteWolf'' settings work this way, because they're six games and counting (seven if you include the corebook setting) set in separate time periods of the same universe, but the decision was made to not have a set future for any individual game. As a result, if you're playing in a chronologically later game, then the earlier games are considered canon, but if you're playing an earlier game, later games are only "possible futures" and nothing is canon past the start date. This also ties into how one of the major superhuman characters of the continuum is said to have traveled many different timelines.
* ''Webcomic/GrimTalesFromDownBelow'' is said by Creator/{{Bleedman}} to be only a possible BadFuture for his other webcomic, ''Webcomic/PowerPuffGirlsDoujinshi''.
* Happened with two popular ''TabletopGame/Warhammer40000'' [[FanFic fan fictions]] - in ''Fanfic/TheAgeOfDusk'' the Necrons unleash a devastating attack on the Tau, almost destroying their empire and entire race, in order to prevent the possible future known as ''[[http://www.bolterandchainsword.com/index.php?autocom=ineo&showarticle=411 Rise Of Tau]]'' from happening.
* Arguably the case between ''Series/{{Titans|2018}}'' and ''Series/DoomPatrol2019.'' The Doom Patrol were introduced on ''Titans'' as the group that helped raise Beast Boy. The SpinOff has most of the actors from that episode reprise their roles, but the story presented doesn't really allow for the possibility that Beast Boy was part of the group, along with everyone being even weirder and [[AdaptationalAngstUpgrade angstier than they were before]], and some of the actors and showrunners made statements in interviews that the two shows weren't in continuity with each other. The ''Titans'' episode also had no reference to Crazy Jane, who's a core member of the Doom Patrol in ''Doom Patrol''. A view of the Multiverse in the Series/{{Arrowverse}} Crisis Crossover ''[[Series/CrisisOnInfiniteEarths2019 Crisis on Infinite Earths]]'' gives different universe numbers to the two shows.
* Similarly ''Series/SupermanAndLois'' stars the actors who played the titular characters in the Franchise/{{Arrowverse}}, but it quickly becomes clear that this Superman ''doesn't'' have a cousin called Supergirl who provides a tangible connection to Krypton, and Season 2 outright states that there are no powered heroes on Earth except Clark, although Sam Lane is aware of alternate universes where this isn't the case. Which doesn't stop them being part of the John Diggle CrossThrough.

!Examples of Bait-And-Switch Continuity:
* Creator/ImageComics operates on this rule - their comics exist in one world only when crossovers take place and events from one series may be referenced in another only if the creators wish it. It's especially visible in ''ComicBook/{{Invincible}}'' #60 -- comics that featured appearances of probably every single Image Comics hero aside from ComicBook/BombQueen and you won't find a single reference to those events (including the destruction of several cities) anywhere but in ''Invincible'' and ''ComicBook/TheAstoundingWolfMan''.
* Creator/AkiraToriyama's ''Manga/DrSlump'' had a tendency towards NegativeContinuity where Arale could split the world in half and have everything back to normal by the next chapter. His following series ''Manga/DragonBall'' actually featured the cast of ''Dr. Slump'' in one of the storylines, despite much of ''Slump'''s logic or continuity (or lack thereof) making little to no sense in the context of ''Dragon Ball'', the whole encounter playing off almost as a BigLippedAlligatorMoment to anyone not familiar with his original series.
* Most inter-company comic book crossovers worked like this until 1996's ''DC Versus Marvel.'' Prior to that miniseries, when ComicBook/{{Superman}} met ComicBook/SpiderMan, the ComicBook/TeenTitans met the ComicBook/XMen, or [[ComicBook/Gen13 Gen13]] met ComicBook/SpiderMan, the assumption for the duration of those stories was that the two characters had always been part of the same universe and had simply never met before. Since ''DC Versus Marvel,'' such crossovers have been much more likely to involve [[ParallelUniverse parallel universes.]]
* ''WesternAnimation/TheSimpsons'' has had crossovers with ''WesternAnimation/TheCritic'' ({{downplayed|Trope}} in that the only elements from that show to appear are Jay Sherman himself -- whose character design was tweaked to fit in with ''The Simpsons'' -- and ''[[ShowWithinAShow Coming Attractions]]''[[note]]the show's version of the Devil would have made a cameo at the end of [[HopelessAuditionees the auditions for Burns's movie]], but his appearance was ultimately cut[[/note]]), ''WesternAnimation/FamilyGuy'' (which poked fun at their different art styles a few times), and ''WesternAnimation/{{Futurama}}'' (which [[ElephantInTheLivingRoom ignored the obvious skin color differences despite the two shows having the same art style]]), but since the show mostly runs on NegativeContinuity, they leave little impact on the show itself (with the notable exception of a deactivated Bender appearing briefly in "Cue Detective" and "Throw Grampa From the Dane"). Notably, characters from both shows made a few cameo appearances in each other before their crossover episode, but they're just in the service of throwaway gags, and the crossover episode itself depicts them as never having met before. There was also an episode of ''Futurama'' when the team found a Bart Simpson toy on a garbage asteroid.
* Each season of ''Franchise/SuperSentai'' and ''Franchise/KamenRider'' is largely standalone, but whenever there's a crossover all bets are off. What makes things confusing is that sometimes the two series/seasons are explicitly crossing between {{Alternate Universe}}s to meet each other (''Series/KamenRiderDecade'' is the most obvious example), but sometimes they act as if they share a world even when their settings are completely incompatible (for example, ''Series/KamenRiderExAid'', set in modern Japan, saw an out-of-nowhere cameo by Lucky of ''Series/UchuSentaiKyuranger'' when ''Kyuranger'' is a far-future SpaceOpera where most of the universe (Earth included) has been under oppression for hundreds of years).
** ''Kamen Rider'' seemed to vaguely have a SharedUniverse in place for most of the Heisei era (2000-2019), with past Riders existing but [[SupermanStaysOutOfGotham staying out of "Gotham"]] for one reason or another (often that their own series ended with them losing or sealing away their powers). ''[[Series/KamenRiderKabuto Kabuto]]'' and ''[[Series/KamenRiderBuild Build]]'' are exceptions, explicitly put in their own separate universes because both of them had major disasters in their backstories[[note]]In ''Kabuto'', a meteor struck Tokyo in 1999, destroying Shibuya; in ''Build'', an alien artifact created gigantic walls that split Japan into three separate nations in 2007[[/note]] that other series couldn't just HandWave away. ''[[Series/KamenRiderZiO Zi-O]]'' ended with the main character nearly causing a TimeCrash by merging all 20 Heisei universes together, then putting them all back in their own universes just in time for [[Series/KamenRiderZeroOne the Reiwa era]].

!Examples of Divorced Continuity:
* Creator/ImageComics separated their original universe into a bunch of lesser ones in the ''Shattered Image'' event. Since then, each sub-publisher has its own universe that coexists with others in Bait-And-Switch continuity, with the exception of the Creator/{{Wildstorm}} universe, which was bought by Creator/DCComics, and Creator/RobLiefeld's universe, for the period of time that he left Image.
* ''Series/{{Dallas}}'' and its SpinOff, ''Series/KnotsLanding,'' split up over Bobby's fate on the parent show. Bobby's brother Gary was the main character on ''Knots Landing;'' naturally the death affects him, and later in the season [[DeadGuyJunior he names his new son after Bobby]]. Infamously, ''Dallas'' would later RetCon an entire previous season, including Bobby's death, as AllJustADream. Bobby remained dead in ''Knots Landing,'' however, and the shows never crossed over again.
* ''Fanfic/BothSyllables'' was a popular fanfic series with a few {{Recursive Fic}}s, including ''[[https://www.fanfiction.net/s/5413714/1/Policy-of-Truth Policy of Truth]].'' Eventually the main series was [[DeadFic abandoned]] and taken down from the internet. At that point ''Policy of Truth'''s author decided to take the story (and later, its sequel) in a different direction by introducing [[spoiler:Zim]] and [[spoiler:Tak]]. ''Both Syllables'' also established Dib's full name as "Dilbert Putchel," while [=PoT=] went with the [[AscendedFanon now-canonical]] "Dib Membrane."
* ''WesternAnimation/HazbinHotel'' and ''WebAnimation/HelluvaBoss'' exist in the same setting and the cast of Helluva Boss was originally intended to be supporting characters of Hazbin Hotel. However, the shows were split after it became clear that Helluva Boss covered too much story for Hazbin Hotel. Then, Hazbin Hotel was picked by A24, forcing a clearer divorce between the shows for copyright reasons. As a result, Helluva Boss ''never'' sees any action in the Pride Ring (which is referred exclusively as Hell in Hazbin Hotel) and explores other parts of Hell or the mortal realm that the cast of Hazbin don't get to see. To still have demonic power players in Helluva Boss, the Ars Goetia were created as a replacement for the Overlords, with Stolas himself modelled after a particular Overlord from Hazbin Hotel that has since been removed from continuity. That said, shared universe elements persist between the two shows. Hazbin Hotel still features Hellborn demons like Imps, Hellhounds and Loan Sharks that are commonplace in Helluva Boss; Fizzie robots based on Fizzarolli can be seen in some scenes; Lucifer has a diagram of the Seven Rings in his workshop; and the character of Mimzy has a tattoo of Mammon's logo. Meanwhile, the Overlords, Carmilla Carmine and Lucifer are all name-dropped at various points in Helluva Boss, with less prominent Hazbin Hotel characters such as Travis even making brief cameos.

!Examples of a Mixed Approach:
* The ''Franchise/DoctorWhoExpandedUniverse'' is ''generally'' in One-Sided Continuity with the televised Franchise/{{Whoniverse}}, barring occasional throwaway references (the most prominent being the Eighth Doctor listing all his Big Finish Audio companions in [[Recap/DoctorWho50thPrequelTheNightOfTheDoctor "The Night of the Doctor"]]) and the inclusion of concepts in the revival seasons that were first introduced in expanded media (e.g. a TARDIS dying when its pilot does, the Doctor telling the year by smelling the air, the Doctor being able to erase memories, etc.). The relationship of the various spin-off media to ''each other'' is ... confused, often being split not even by series, but by ''author'', so if, for instance, Author A believes that the ''Literature/EighthDoctorAdventures'' and ''AudioPlay/BigFinishDoctorWho'' are in continuity with each other, they would write for ''both'' series accordingly, while if Author B believes they're alternate timelines, they would do likewise. (This does not stop the [=EDAs=] by both authors being in continuity with ''each other'', of course.) The official position of both companies is simply one big ShrugOfGod. Similarly, the ''Magazine/DoctorWhoMagazine'' comic strip went through a period of being in continuity with the ''Literature/DoctorWhoNewAdventures'', then firmly decided it wasn't. It's also sometimes been in continuity with the Franchise/MarvelUniverse, although that can probably be explained away by the Doctor jumping universes on occasion.
* The creators of the ''Series/TheXFiles'' and ''Series/Millennium1996'' just couldn't seem to decide if the two shows share a universe or not. The first instance of intershow continuity occurred in the Millennium's Season 2 episode, ''Jose Chung's Doomsday Defence'', which featured the author, Jose Chung, who had previously appeared in a Season 3 episode of X-Files. Later episodes of Millennium's Season 2 and Season 3, however, included several references to X-Files suggesting it is a TV show that exists in the Millennium universe, including an X-Files ThemeTuneCameo in one sequence. Then came the FullyAbsorbedFinale of Millennium which took place over the course of an X-Files episode, seeing the main casts of both shows interacting with one another for the first (and last) time.
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