History SeriesContinuityError / LiveActionTV

** In another episode, Sheldon asserts that he never forgets anything. Later in the same episode, when he is listing all of the actresses who have played Catwoman, Howard points out that he left out Lee Meriwether. "Oh. I forgot about Lee Meriwether". Unfortunately, it doesn't appear that the writers caught the joke. Justified as Sheldon is known for massively overestimating his own intelligence. [[note]]He also forgot Maggie Baird, who played the role in ''Series/BirdsOfPrey2002'' for all of one scene, but that one's presumably on the writers.[[/note]]

* ''Series/HappyDays'': Fonzie recalls having his tonsils removed as a child, yet a later episode has him get a tonsillecomy as an adult.

** DependingOnTheWriter, Blanche can have between 4 and 6 children. [They eventually tried to knock these together, however; in one instance, she had previously specified she was talking about her four sons (she was offering to give Dorothy one of her sons in exchange for keeping a Mercedes they couldn't afford, saying "I have had four kids, I have never had a Mercedes.") All of her kids were named however: Biff, Doug, Skippy, Matthew, Janet, and Rebecca.]

*** She tells a character in Season 1 that she lived at St. Basil's orphanage until age 18, but Season 3 has an ep with a big plot point being that Stella lived with a foster sister who was molested and eventually killed her attacker, and that the two of them were so close they became [[BloodBrothers blood sisters]]. Late in Season 5, this is retconned that her mentor had "rescued" her from foster care and took her to live in the orphanage where he taught school.

** In "Our 'Cops' is On!", the first episode of ''Series/{{COPS}}'' filmed in Camden County was said to have taken place in 2003. In "Our Other ''Cops'' is on!", the second episode of ''COPS'' filmed in Camden is said to have taken place on the first Independence Day since 9/11, placing it in 2002 and it contains references to the previous episode of ''COPS'', so it couldn't have been filmed before it.

* In "I Hate Frasier Crane", Martin says that the killer in the Weeping Lotus case tried to stuff the body into a bowling bag. In "Retirement is Murder", he says that the victim was killed at the beach and tried to write a message in the sand, in which case it only makes sense that she was still alive when the killer left the scene.

** There are some problems concerning the ages of Martin and Frasier. It is established that Martin was 21 years old and married to Hester when Frasier was born. There is another episode where Martin recalls being single at 22.

** The notorious UNIT dating problem: In "Pyramids of Mars", Sarah Jane Smith is from 1980, and the last time she was there, the Brigadier was still heading UNIT ("Terror of the Zygons"). In [[Recap/DoctorWhoS20E3MawdrynUndead "Mawdryn Undead"]], the Brigadier retired in 1976, taking up a position as mathematics teacher through 1983. Lampshaded in the series 4 episode [[Recap/DoctorWhoS30E4TheSontaranStratagem "The Sontaran Stratagem"]], when the Doctor tells Donna he used to work for UNIT in the '70s... or maybe the '80s... (this joke has been repeated numerous times since, including in 50th anniversary special [[Recap/DoctorWho50thASTheDayOfTheDoctor "The Day of the Doctor"]], where it's implied that some form of "dating protocol" exists). This is compounded by the fact that in a deleted scene from Sarah Jane's first serial, [[Recap/DoctorWhoS11E1TheTimeWarrior "The Time Warrior"]], she was scripted to explicitly tell Lynx she had come from the year 1974. This apparently stemmed from a dispute between the writers of the show as to whether the UNIT years should happen in the present day or slightly in the future (another such continuity snarl line happened in [[Recap/DoctorWhoS10E5TheGreenDeath "The Green Death"]], where one of the Global Chemicals employees tells the Brigadier that they'd recently swapped out their cutting gear for a "thermal lance").

* ''Series/{{MASH}}''

* ''Series/{{Monk}}''

* ''Series/TheXFiles''

* In the original run of ''Series/WKRPInCincinnati'' Herb Tarlek acknowledges his alcoholism. When the series was revived in syndication he was a social drinker again.

* ''[[StarTrek/SeriesContinuityError Star Trek]]''

* ''Franchise/StarTrek'':
** In the ''TNG'' episode "[[{{Recap/StarTrekTheNextGenerationS6E4Relics}} Relics]]", Scotty is released from a transporter buffer where he was trapped for 75 years and initially believes that Geordi and Riker were sent by Kirk. However, ''Film/StarTrekGenerations'' reveals that Scotty was present when Kirk was sucked into the Nexus from ''Enterprise-B'' (this was due to Scotty being placed in the movie at the last minute since Creator/LeonardNimoy wasn't available). The ExpandedUniverse attempted to {{Retcon}} this by saying that Scotty never really believed Kirk was dead.
** In their first appearance, the Ferengi were aggressive, militaristic imperialists. In later appearances, they are portrayed as craven, greedy people with few cultural arts outside peddling and trading. This was an AuthorsSavingThrow; they'd planned to make the Ferengi the new [[BigBad Big Bad Aliens]] of the franchise, and they didn't realize until the episode was already wrapped and aired that they'd utterly failed at it. So they cut their losses, rewrote the Ferengi (and changed their uniforms to something less silly), and brought back the [[MagnificentBastard Romulans]]. (The ExpandedUniverse has a cute explanation for this: the HumanPopsicle stock broker from the 20th century who also appeared in the episode where Romulans first reappeared was eventually made the Federation ambassador to the Ferengi homeworld. This lead to the revelation that the hostilities were due to the two species not being able to understand each other, and the unfrozen stock broker was able to bridge the divide.) The timeline on this is also sketchy. In 2364, it's stated that the Federation (specifically, humans) and the Ferengi have never even seen each other and know nothing about each other. However, in the ''[[Series/StarTrekDeepSpaceNine Deep Space Nine]]'' episode "[[Recap/StarTrekDeepSpaceNineS02E08NecessaryEvil Necessary Evil]]", flashbacks show Quark in his bar on what was then Terok Nor (and it seemed like he'd been there a while) by the time Odo arrived in 2365. In order for this to track, it would have to be the case that they had made contact and developed some level of rapport with one major power (Cardassia), while knowing nothing about another (the Federation) beyond vague rumors and speculation. If nothing else, why wouldn't they at least get the (albeit biased) basics about the Federation from the Cardassians?
** The original series episode "[[{{Recap/StarTrekS1E22SpaceSeed}} Space Seed]]" was made during a time when a specific year wasn't yet assigned to the canon, so it references things in blocks of time... but misses the mark by a hundred years when ''Film/StarTrekIITheWrathOfKhan'' came out. Whoops.
** The Borg story has a sketchy chronology. Q set Picard's ''Enterprise'' thousands of light-years to find the Borg for the first time, and eighteen months later they came looking for Earth. Guinan identified the Borg in their introductory episode and it was later revealed that Guinan and her people migrated during Kirk's time. ''Voyager'' introduces Federation scientists (Seven of Nine's parents) studying the Borg long before Picard's first contact. It messed up what was inferred in the original episode, but it does make some sense that Guinan's people could have reported it to the Federation and it just didn't become common knowledge until the official first contact.
** In the Borg's first appearance in "[[{{Recap/StarTrekTheNextGenerationS2E16QWho}} Q Who]]" they're only interested in "consuming" technology, and ignore other lifeforms unless they see them as a threat. When they take Picard in "Best of Both Worlds", he's chosen to be a spokesman, not a drone. It's only after this that we're told assimilating other lifeforms is their standard MO, and ''always was''.
** "[[{{Recap/StarTrekTheNextGenerationS1E25TheNeutralZone}} The Neutral Zone]]",
*** The vanished outposts were meant to be foreshadowing of the Borg (in "Q Who?", they encounter an identical pattern of destruction after Q displaces them), implying that the Borg were probing the edge of Federation space even before Q made formal introductions. This is never mentioned again, and Guinan would later claim that, thanks to Q's intervention, the Borg discovered humanity centuries sooner than they ought to have done.
*** "The Neutral Zone" established that the Romulans had been in a self-imposed isolation for a good fifty years, choosing now to come out of it because of the attack on their outposts. Later episodes bring up encounters with the Romulans, from [[Series/StarTrekDeepSpaceNine Garak]] having worked at the embassy to Romulus from Cardassia, at the same time as the deaths of several high level Romulan officials ([[SuspiciouslySpecificDenial which was pure coincidence]]), and a handful of major battles with the Klingons, one at Khitomer (which is on the Federation border, the attack being how Worf was adopted by a human couple), another at Narendra III, [[Recap/StarTrekTheNextGenerationS3E15YesterdaysEnterprise the battle that claimed the Enterprise-C,]] and [[Recap/StarTrekTheNextGenerationS1E13AngelOne a previous episode]] mentioning that there was a Romulan incursion at the Neutral Zone that required the Enterprise to show up and wave the flag to spook them off.
** Data's cat was repeatedly referred to as male since it was introduced, then suddenly became female in the last season and even had kittens. Spot was also a different breed in his/her first appearance.
** In "The Naked Now", Tasha tells Data she was "abandoned" at the age of five, suggesting that her parents just up and left her. In "Legacy", Ishara says that their parents were ''killed'' (and since Ishara was a baby at the time, anything she knows about what happened to them would have had to come ''from'' Tasha, so it doesn't make sense in-universe for them to have different stories).
** There were continual goofs in whether Lieutenant Commanders are referred to as "Lieutenant" or "Commander" formally. They could probably have gotten away with either regardless of real-world behaviors if they had just chosen one and stuck with it.
** When the Trill were first introduced in a ''TNG'' episode they were very different than when they became regular ''[=DS9=]'' characters. To start with, they had facial ridges and no spots unlike their ''[=DS9=]'' appearance.[[note]]The change was made because they hired model Terry Farrell to play Dax, and didn't want her to lose any of her FanService appeal[[/note]] The symbiotic nature of the Trill was also different, implied this is the natural state of the entire species, rather than only certain Trill being selected as hosts, and it's implied that the host contributes little or nothing with the symbiont being the "true" Trill, whereas Jadzia Dax made it clear each host creates a completely different individual when joined, ''and'' that joined Trill are a small minority, with the vast majority of Trill never getting a symbiont. Lastly, the Trill are stated by Picard to be a relatively unknown species, to the point that their symbiotic nature was a total shock. ''[=DS9=]'' established that at least one joined Trill -- the previous Dax host -- was a famous Federation ambassador and Starfleet officer who had been Sisko's mentor for most of his career. Even if he was the only Trill ever to serve in Starfleet at that point, they should have had at least some basic awareness of the species. In addition, it's a major plot point in Season 7 of ''[=DS9=]'' that Ezri had to become the permanent Dax host, even though she never wanted/intended to be Joined, because she was the only Trill onboard, and that was supposedly the only option when Dax could no longer survive outside a host. But ''TNG'' had already established that a non-Trill can act as a temporary host (which Trills can't do, because their bodies will fully integrate with the symbiont within a day or so) with no long-term ill effects. Why not just put Dax in a willing non-Trill volunteer (or even a series of them, if necessary) until they got to the Trill homeworld? Also, in season 3 of ''Series/StarTrekDiscovery'', the Trill treat a human acting as a host to a Trill symbiont as an impossibility. Have they forgotten that Riker has already done that? In addition, ''[=DS9=]'' established that nearly half of the humanoid Trill population is capable of serving as hosts to symbionts, but the government has been keeping that a secret. But in ''DIS'' they mention how their population of viable hosts has been severely depleted by [[spoiler:the Burn]]. One would think that the government would remove the secrecy at this point in order to allow most Trill to join.
** In the ''Series/StarTrekDeepSpaceNine'' episode "[[{{Recap/StarTrekDeepSpaceNineS02E12TheAlternate}} The Alternate]]", Sisko strongly implies that his father is dead. This contradicts later episodes where his father is very much alive and running a restaurant in New Orleans.
** O'Brien's exact rank is inconsistent in his first few appearances in ''TNG''; he's an ensign in one episode, a lieutenant in another, and his position on the ship changes. Season 2 established him as a Chief Petty Officer, right around the time his character was also named for the first time.
** In ''Series/StarTrekDeepSpaceNine''; in one of Ezri Dax's early episodes where she's having trouble dealing with the responsibilities of being Dax's host, Sisko teases her by suggesting she can return to Trill and become one of the caretakers of the immature symbionts. He then goes on to describe that her duties would entail stirring the mud in the vats which contain the immature symbionts. The trouble is that we've already seen the subterranean caverns he's talking about, and the immature symbionts swim around in immense subterranean rivers, not mud.
** In the ''Series/StarTrekTheOriginalSeries'' episode "[[Recap/StarTrekS2E23TheOmegaGlory The Omega Glory]]", costumer William Theiss gave crew members of the USS ''Exeter'' their own uniform patch instead of the chevron worn by the ''Enterprise'' crew, under the mistaken impression that every starship had its own insignia. [[http://www.startrek.com/article/starfleet-insignia-explained He was corrected on this point by Robert Justman]], who explained that the chevron didn't denote the ''Enterprise'' but rather was branch insignia for personnel assigned to starships. Theiss didn't make the mistake again, but the error spawned a fan theory that in the 2260s, each of the twelve ''Constitution''-class starships had their own insignia, and that the ''Enterprise'' chevron was adopted throughout Starfleet as a result of the ship's {{fame|dInStory}}. This became so endemic that the costumers of ''Series/StarTrekEnterprise'' gave dead USS ''Defiant'' crew members their own unit patch in "[[Recap/StarTrekEnterpriseS04E18InAMirrorDarkly In a Mirror, Darkly, Part I]]", despite them having worn an ''Enterprise''-style chevron when they disappeared from the prime universe in "[[Recap/StarTrekS3E9TheTholianWeb The Tholian Web]]".
** The TOS episode "[[Recap/StarTrekS1E18Arena Arena]]" treats the Gorn as though the Federation have never run into them before, under any circumstances, ever. However, in the ''Series/StarTrekStrangeNewWorlds'' episode "[[Recap/StarTrekStrangeNewWorldsS1E04MementoMori Memento Mori]]", the ''Enterprise'' (under Pike's command) has to fight Gorn ships, with La'an recalling her own childhood experience as a prisoner of the Gorn. The show takes place nearly ten years before TOS, so either Kirk was misinformed or it's a minor RetCon that claims that while the Gorn have been known by Starfleet, they've never been seen in person (except by La'an).
** In "[[Recap/StarTrekS1E9DaggerOfTheMind Dagger of the Mind]]," Spock, when about to perform the first MindMeld in the franchise, mentions he's never done one with a human before. In the same SNW episode, which, again place about a decade before that one, he mind-melds with La'an, a human.
** In "[[Recap/StarTrekS2E1AmokTime Amok Time]]", Nurse Chapel is shocked at the existence of Spock's fiancée T'Pring. Except she has already met her "[[Recap/StarTrekStrangeNewWorldsS1E05SpockAmok Spock Amok]]" and even gave Spock relationship advice a decade prior.

* ''Series/StrangerThings'': Will's birthday was established to be March 22nd in Season 2, but Season 4 later has an episode take place on March 22nd with no mention of it being Will's birthday, which the Duffers admitted was because they forgot about it.

* ''Series/ATouchOfCloth'', perhaps uniquely, ''deliberately creates a continuity error'' purely for RuleOfFunny. Early in the first episode of Series 2, Tom Boss off-handedly mentions that a pound of heroin has gone missing from the vice squad tuck shop. Later in the episode, once Jack Cloth has gotten involved in the case and gone undercover to infiltrate Macratty's gang, what does he use to gain Macratty's trust? [[ChekhovsGun A pound of heroin from the vice squad tuck shop]]… the same one that was stolen ''before he was even involved in the case''. This being a parody with NoFourthWall, [[LampshadeHanging the resulting continuity error is soon pointed out to Jack by another officer]]… and as Jack rants that he doesn't need to obey the laws of continuity, ''[[SugarWiki/FunnyMoments his beard briefly vanishes]]'' [[SugarWiki/FunnyMoments only to reappear when the camera angle changes]].

** In "Our ''COPS'' is On!", the episode of ''Series/{{COPS}}'' filmed in Camden County was said to take place in 2003. In "Our Other ''COPS'' is on!", the second episode of ''COPS'' filmed in Camden is said to have taken place on the first Independence Day since 9/11, placing it in 2002 and it contains references to the previous ''COPS'', so it couldn't have been filmed before it.

** In "[[Recap/CommunityS5E11GIJeff GI Jeff]]", Jeff states he turned 40. However, in "[[Recap/CommunityS2E17IntroToPoliticalScience Intro to Political Science]]" Jeff claims he was 19 when he auditioned for ''Series/TheRealWorld'' Seattle, which would have been sometime in 1997, meaning Jeff would've been born in 1978, making him 36 at the time of the season. This is further contradicted by ''[[Recap/CommunityS4E05CooperativeEscapismInFamilialRelations Cooperative Escapism In Familial Relations]]'' in which Jeff mentions having been in 7th grade "22 years ago". Assuming Jeff was 13 in 7th grade, this would make him 35 at the time of the episode, and again give a birth year of 1978.

** In "[[Recap/CommunityS5E11GIJeff GI Jeff]]", Jeff states he turned 40. However, in "[[Recap/CommunityS2E17IntroToPoliticalScience Intro to Political Science]]" Jeff claims he was 19 when he auditioned for ''Series/TheRealWorld'' Seattle, which would have been sometime in 1997, meaning Jeff would've been born in 1978, making him 36 at the time of the season. This is further contradicted by ''[[Recap/CommunityS4E5CooperativeEscapismInFamilialRelations Cooperative Escapism In Familial Relations]]'' in which Jeff mentions having been in 7th grade "22 years ago". Assuming Jeff was 13 in 7th grade, this would make him 35 at the time of the episode, and again give a birth year of 1978.

** In "[[Recap/CommunityS5E11GIJeff]]", Jeff states he turned 40. However, in "[[Recap/CommunityS2E17IntroToPoliticalScience]]" Jeff claims he was 19 when he auditioned for ''Series/TheRealWorld'' Seattle, which would have been sometime in 1997, meaning Jeff would've been born in 1978, making him 36 at the time of the season. This is further contradicted by ''[[Recap/CommunityS4E5CooperativeEscapismInFamilialRelations]]'' in which Jeff mentions having been in 7th grade "22 years ago". Assuming Jeff was 13 in 7th grade, this would make him 35 at the time of the episode, and again give a birth year of 1978.