Continuity Lock Out

"Ben and I decided that we needed more strips and punchlines that only make sense to hardcore readers. Look forward to jokes so inaccessible even we, the authors, don't get them."

- Lewis, Terror Island #200

The writers have let the mythos they have generated get so thick and convoluted that a new reader/viewer has very little chance of understanding the significance of anything. They are locked out of understanding the story by all the reliance on continuity.

This is one of the main bones of contention between creators and executives. Executives want each episode to potentially bring in new audience. Creators want to entertain the audience they have. In a rare case of this wiki taking the side of the executive meddlers, we have to admit that continuity lock-out is never caused by the execs. It has to be written.

The standard answer to this issue is the "Previously On..." segment: many shows on this list open each episode with a short capsule summary of events you should be aware of. Of course, Previously Ons have their own drawbacks, such as inadvertently providing spoilers or flat-out not working. The better answer is Better On DVD: after all, the best way for anyone to understand any show is to buy the DVDs and watch it from the beginning, sometimes more than once or with the help of fan annotations.

Why bother with the intense continuity at all? Simple: An intricate series-spanning plot often results in a stronger and more interesting overall show. You may not catch as many fans, but the ones you do get are yours for life. This does mean that you have be sure to rope in as many as possible early on before the Lockout effect takes hold to make the effort worthwhile.

Some Long Runners and certain mediums (such as novels) are designed to be engaged with in a linear multi-volume fashion over a period of time, and the authors can't reasonably be expected to keep everything entirely accessible to a newcomer if they want to engage in any meaningful plot or Character Development; if you start reading a seven-volume series at volume five and find yourself hopelessly lost, then you arguably have only yourself (or in some cases the publisher) to blame.

A Compressed Adaptation might cause this. In Web Comics, this can be the impetus for an Archive Binge or a justification for Archive Panic.

Anime & Manga

 * Gundam--
 * This happened with the original UC timeline, which is one of the main reasons Alternate Universe series were made. It was also a major driving force behind the creation of Metal Armor Dragonar; Bandai wanted to bring in fans who might have otherwise been stymied by the existing Gundam mythos and were ready to switch production to Dragonar if it outperformed Gundam ZZ. It didn't, but remains a cult favorite.
 * Somewhat remedied by the easy-to-follow-if-hard-to-grab-all-the-nuances Mobile Suit Gundam Unicorn.
 * Parodied in an episode of Sayonara Zetsubou Sensei: Itoshiki was driven to despair by, among other things, the fact that his own show had so many running gags that it was impossible for new viewers to understand. Hence, he changed the screen so that it displayed constantly changing information about all the characters and their personalities, and went on to explain several of the nominal puns and running jokes.

It was also parodied in that they quickly grew tired of those longtime viewers who knew the show so well they saw all the jokes coming.
 * Fullmetal Alchemist. Same goes for the 2003 anime adaptation, especially if you're watching the OVA and didn't see the last few episodes.
 * Naruto is susceptible to this during its arcs.
 * Given the length of Jo Jos Bizarre Adventure, it's natural that this can happen. However, the author is generally good at keeping new readers up to date, as every volume of the manga has a timeline of the series, and the various relationships outlined. The first (duh), third, fourth, and seventh parts of the series can easily be picked up and read without any previous knowledge about the series. The others require some background knowledge, but that's it.
 * Death Note, mostly due to the Gambit Pileup nature of the series. It's possible to jump in within the first ten episodes or so, but after Light and L actually meet each other, forget that.
 * Neon Genesis Evangelion inverts this, in that you don't understand anything about the overall plot coming OUT of the series. Then again, you have a pretty good idea of how fucked up everyone's mind is at least. But do we REALLY need to know what Shinji, Misato, and umm....Gendo do when they're feeling "lonely"?
 * As punishment for anybody skipping the Bount Arc, the producers of Bleach left the three mod-souls so people could go "WTF who are these guys" and be forced to see their origins. But then again, they're just there to create even more filler so no one would blame you for skimming a synopsis or twelve.
 * Kariya from the Bount Arc also makes a Cameo appearance during Ichigo's Vizard training, which pretty much makes anyone go "WTF who's that?"
 * Both averted and played straight in Ranma One Half; the show regularly makes references to characters, events, or character quirks with very little attempt to explain them to newcomers. On the other hand, if you've seen the first three seasons (or read about the first 10 volumes of the manga) you can pretty much watch the rest of the episodes in any order, and at the very worst you won't recognize a returning minor character.
 * Given that One Piece has been running since 1997, Eiichiro Oda understandably tries to avoid locking out his readers, which can be difficult given the fact that almost everything and everyone in the series is of some importance even if you don't follow the series from the start. Given that collecting every volume of the story released so far will set you back a few hundred dollars, he understandably puts short flash-backs into the story as well as summaries of the various arcs. To offset this, volume 50 is clearly labelled as a good "starting point", complete with recaps, backgrounds and a new direction for the story.
 * Recent chapters of Mahou Sensei Negima are heading this way; the later arcs make little or no sense unless you have a very good grip of the earlier ones. This is even more pronounced with the OVAs, which make no sense whatsoever unless you've read almost the entire manga.
 * Of course, the OVAs were only ever released as bonus material for certain Japanese limited edition volumes of the manga, so it's not like casual fans have access to them anyway. Assuming we're talking about the Ala Alba ones and not Spring and Summer, which were primarily Fan Service episodes.
 * Would you believe a simple Fan Service-laden Unwanted Harem show like To Love Ru has this? If you only watch the anime, you'll never find out what's the deal with Celine, where did she come from, and why she's suddenly living with the main cast. Or, until the second anime season, where did Oshizu get herself a new body. Also, the new manga To Love Ru Darkness makes no effort of helping newcomers on telling who's everyone.
 * Tsubasa Reservoir Chronicle. It is a Massive Multiplayer Crossover that requires you to read Xxx Holic in order to understand what's going on in the background. Even then, you'd probably still be a little lost unless you also happened to have read Cardcaptor Sakura (which, admittedly, is probably the reason why you're reading Tsubasa in the first place), AND X 1999 AND Tokyo Babylon by extension.
 * Pokémon Special has its instances of this, with current, important plot points coming from previous-generation chapters.

Comic Books

 * This is particularly prevalent in comic book series, more so than television or film, because while most TV shows run for a maximum of a few hundred episodes (most of which are easily obtainable one way or another) some comic book series run for much longer. (Like Superman: Consistently in print since the 1930s). This, and the fact that comic books can be incredibly rare (with the auction prices this entails), ensures that most new readers are just going to either give up or ignore most of the last 70 years of continuity.
 * This was the reason given for DC Comics' first Cosmic Retcon, Crisis On Infinite Earths, back in 1985: that things were getting too confusing for the fans (in actuality, it was getting too confusing *for the writers* but they didn't want to admit it.)
 * Chris Claremont took this to eleven with his out-of-continuity miniseries X-Men: The End, which attempts to bring every subplot of thirty years to a satisfactory conclusion.
 * During his run on X-Men, Grant Morrison stated that he wanted to make the book more accessible to new readers by avoiding mentioning past storylines beyond vague summaries. Once he left the book, the subsequent writers went right back to the older, continuity-heavy storytelling style.
 * The first movie did far better business than expected. A number observed that not only were the comics mired in their own complicated storylines and prominently featuring non-movie characters instead, but that Marvel didn't even try to tie-in to the movie. Consequently, the comics saw no boost in readership as the movie raked in millions, so the trope was cited. Crossover traffic may not have happened regardless and this next part may not be true, but the trope is widely believed to be the reason why Bob Harras was fired from Marvel.
 * Fred Perry's Gold Digger has managed to achieve a degree of Continuity Lockout nearing that of The DCU, despite having only existed since the early '90s and consisting only of one main title, a short-lived spinoff, and a few early crossovers with Ninja High School. Miss a few issues and you're likely to be met with a completely different set of cast members some of whom haven't shown up for a few years, sometimes not even mentioning the main characters.
 * He is attempting to combat this with the 101st color comic, basically set a few years after the 100th and having some new archaeologists under the tutelage of Gina. Who is also a professor.
 * The Gail Simone run on Wonder Woman was pretty continuity-heavy and sales fell sharply during it, with the writer herself later lamenting that her run might have been confusing to new readers. DC hired J Michael Straczynski to replace Simone and bring in new readers with a highly-publicized storyline that took place in a more accessible Alternate Continuity. Brian Azzarello took Wonder Woman back to a more classic take, but he has said he will be making a deliberate effort to avoid bringing up past storylines and characters so as not to alienate new readers.
 * Kurt Busiek actually managed to avoid this with Untold Tales of Spider-Man. Instead of being a retcon or anything similar, it was early stories set 'in-between' the very first Spider-Man stories. If you had read the original issues it made Untold Tales more enjoyable, but if you hadn't then it was still no biggie.

Film

 * The more recent Harry Potter films have had this problem in an unusual way. Each individual movie has been more or less comprehensible without reading the books. However, when put into a movie continuity, things don't make sense.
 * As an example, the plot and tension of Order of the Phoenix hinges on the fact that the only person who would admit to Voldemort's return is Harry Potter. The problem is that if you saw Goblet of Fire you know that isn't true. Because the Ministry of Magic clearly has someone in custody who could tell them (or they could magic it out of his head): Barty Crouch Jr, who was last seen alive and going to be taken into custody at the end of the film. Of course, the book of Goblet of Fire had him kinda-killed off. This was not done in the film, and thus you need to read the books in order for the continuous work of films to make sense.
 * An earlier example would be the complete cutting out of Peeves, hence the cutting of the broken Vanishing Cabinet, which became an important Chekhov's Gun in HBP.
 * Not only back story is cut, but some events are treated very badly by the filmmakers. In GoF, the corpse of Barty Crouch Sr. is removed from the woods... only for him and his death to never be mentioned again. (Not even when the assassin reveals himself.)
 * Speaking of the Crouches, the film changes Junior's back story from "believed to be dead" to "still imprisoned in Azkaban". Which may be very confusing for moviegoers who are now expected to believe he could have escaped with nobody noticing while the plot previous film revolved around another escape that was discovered instantly.
 * Moony, Wormtail, Padfoot and Prongs. The movie never says who they are. Then, Harry calls Pettigrew "Wormtail" in the Goblet of Fire movie without explanation. And Sirius is called "Padfoot" in Order of the Phoenix.
 * Plus, it also means that no explanation at all is given for how Lupin instantly recognizes the Marauder's Map for what it is.
 * Nobody believes Voldemort is back in the Order of the Phoenix movie, because they say Harry's words can't be trusted. Never explained why, because they took out all the instances where Rita Skeeter kept bringing out articles that made Harry sound insane and untrustworthy in the previous movie.
 * In Order Of The Phoenix they left out the entire point of Snape's flashback during Occlumeny, which was  It was the massive turning point of his character up until then and they cut it out! They were apparently forced to cut it out, but still.
 * Though it's not entirely obvious this was the worst bit about his memory
 * Dobby and Kreacher are MIA in Half-Blood Prince. Apparently Kreacher was to be excised from the Order of the Phoenix movie as well, until JK stepped in and said "You might need him later."
 * Because the potion book subplot was so shortened in the sixth film, the reveal that makes very little sense. It's clear that this is why the book let Harry be so good at Potions, but even that is minor.
 * They also left out what may be the single most important minor detail in Half-Blood Prince. Specifically,  Harry puts on the stone bust of an ugly wizard in the room of requirement. This   It's not present at all in the movie, so Harry won't know where to look for the 6th   It's possible they might try a workaround with Ginny since she hides the potions book in the movie, but seeing as she's not in on Voldemort's secret in the first place, it's gonna be difficult.
 * No more difficult than leading Harry to the conclusion that  will be, considering that they left out the bits where he and Dumbledore
 * In the end, they just had Harry Did you really think they were going to give Ginny some plot?
 * There is a deleted scene on DH 1 where Harry explains Ron and Hermione what Dumbledore thought the Horcruxes were. Even if it'd been kept in the movie, how Harry knew this would have still been unknown.
 * This trope is actually inverted between Half-Blood Prince and Deathly Hallows Part 1 - a BLAM halfway through Half-Blood Prince that wasn't in the book involves the bad guys burning The Burrow (the Weasleys' House) to the ground. With no explanation at all, it reappears without a scratch in Deathly Hallows.
 * Deathly Hallows Part One does not waste one second bringing people up to speed on who the characters are or what they're doing. Movie critics have not let this pass without comment. It's a very similar case to the Matrix, mentioned below. It also relies heavily on a shard of a magical two-way mirror as a visual and plot device - despite the fact that said mirror has never appeared in the movies before.
 * Though it does do right by Bill Weasley, acknowledging that he and Harry have never met before in the films, and throwing in a reference to how he got his scars (a scene cut from the previous film).
 * All of this is mainly because they decided to make the last three films have the most consistent continuity. Deathly Hallows part 1 and 2, plus parts of HBP, were ridiculously confusing for those who hadn't read the books in entirety. Mostly because they mention some events from the books that were not included in the films. So, if newcomers were to watch all of the movies in order, they would have almost no concept of what was going on by the end.
 * The Star Trek movies (to a large extent) avoided this, save for Star Trek First Contact (which assumed the viewer had some knowledge of the "Best Of Both Worlds" two-parter and Star Trek Deep Space Nine for Worf's location during the cube battle). Several other examples are peppered throughout the films:
 * Data's emotion chip is an interesting example. Star Trek Generations and First Contact both have Data mulling over whether to use the chip or not. New viewers to these films won't understand much of what Data's talking about unless they've seen the earlier seasons of TNG (specifically the fourth- and fifth-season episodes regarding Data, Lore and Dr. Soong).
 * Insurrection averted this trope. According to Michael Piller's unreleased book, Fade In: The Making of Star Trek Insurrection, at least one plan was to have Picard and his crew look for a Federation traitor (a la Heart of Darkness) against the backdrop of the Dominion War (during the point when the Federation was losing ground against the Jem'Hadar). This plan was scrapped due to concerns that theatregoers wouldn't understand the references (which didn't stop them from referencing the aforementioned Deep Space Nine and "Best of Both Worlds").
 * The 2009 Star Trek also largely averted this - seeing as it specifically sets itself as an origin story in a clear alternate continuity (if Handwaved connected to the original through use of the Timey-Wimey Ball). However, the tie-in comic, Countdown, is the canonical last appearance for many of the TNG characters, as well as the only way you'll get to find out the backstory for Nero and his ship (which, in turn, references past elements of the franchise, all the way back to V'Ger).
 * Movies based on comics start with the premise that the movie requires no knowledge of the comic since it's telling its own version of the story. That premise is quickly violated.
 * Example: X Men Origins Wolverine could have used footnotes to explain the significance of its story elements. Since the Weapon X scene was so brief, it could have said "To learn more, please read Weapon X by Barry Windsor-Smith." One benefit is that you get to spend more time with your non-comic-savvy friends explaining the plot. Whether they'll care or not is another story...
 * Origins: Wolverine is relatively unfaithful to the comics anyway (Sabretooth and Wolverine suddenly being brothers, mutilation of Deadpool, Gambit being a bumbling Cajun instead of a smooth one), not to mention its horrible continuity within the film franchise.
 * The Marvel Cinematic Universe does do a good job of adapting the comics while being accessible to a new audience, but the movies often contain numerous in-jokes and Shout Outs that you won't understand unless you are a fan of the comics. Little things like Nick Fury's reference to the "Avengers Initiative" or the Cosmic Cube at the end of Thor likely have no real meaning for a large portion of the audience.
 * Considering that the first is a reference to/foreshadowing for The Avengers and the latter is relevant to Captain America the First Avenger they're less Continuity Lock Out as hints or Sequel Hooks to tie the various films together.
 * Probably the worst is Hawkeye's appearance in Thor. Non-comic fans are left clueless why the movie spent five minutes bringing in a big name actor to play a random wisecracking guy with a bow and arrow, who never appears in the film again.
 * Films set in a historical period tend to leave out a lot of information and twist facts to conform to the plot. You might assume the movie's presentation is accurate if you don't habitually check Wikipedia after the movie.
 * This is definitely one of the reasons why the second and third chapters of The Matrix Trilogy are so polarizing. It is much, much better to watch all three movies on consecutive nights rather than four years between the first and second movie.
 * Peter Greenaway's Luperverse movies, The Falls, The Tulse Luper Suitcases, Drowning by Numbers and several short films, are a deliberate appeal to this trope. His main character, Tulse Luper, generates so much writing and ancillary material about himself (both in canon, and, via Greenaway, In Real Life as well) that no one can write his definitive biography. Lampshaded in his very first appearance in Vertical Features Remake, where a team of academics utterly fails to recreate a lost film Luper made while relying on vague notes and the memories of his collaborators.
 * Ralph Bakshi's take on The Lord of the Rings seem to assume you are already familiar with at least the bare bones of the story, since they refuse to explain anything beyond "And so it was that..."
 * In a bizarre instance where the first sequel has Continuity Lockout, Final Fantasy VII: Advent Children is nearly incomprehensible unless you've played the game.
 * The M. Night Shyamalan film The Last Airbender, based off the TV series Avatar: The Last Airbender, takes most of the key plot points of the series and represents them in a movie format. This trope happens because of the compressed timeframe to tell the story. You never really understand how Aang is trapped in an iceberg, why Katara decides to leave with Aang dragging Sokka along and the nature of why Aang "glows up" in stressful moments is never explained (admittedly, the Avatar State isn't fully explained until the second season, but it happened enough times in the first season to understand its purpose). If you're familiar with the series most everything fits into place.
 * One of the many reasons why The Godfather Part III is polarizing was because of its complete inaccessibility to audience members who had not seen the previous two movies. Wrote Roger Ebert at the time "It is, I suspect, not even possible to understand this film without knowing the first two." However, Ebert still enjoyed the movie and rated it higher than he did for Part II.
 * In what is something of an irony, the producers and executives were a little wary of applying ''Part II" to the second movie partly because they were concerned that people might get the impression they needed to see the first movie in order to understand the second one, which might turn off new audiences. The second movie, however, is generally more accessible, and in general started a trend for numbered sequels.
 * David Lynch's adaptation of Dune is nigh-impossible to comprehend without reading the book, particularly its last forty minutes or so which are an incredibly rushed depiction of two-thirds of the book's length. Especially bad is the scene where Paul decides he needs to ride a sandworm to properly lead his new army, despite the fact that the Fremen ride the worms never having been referenced. In 1984 audiences were even handed playbills before entering the film to explain the plot they were missing.
 * The second Mortal Kombat film Mortal Kombat Annihilation has a huge number of plotholes unless the viewer knows the mythology of the video games. Sub-Zero and Scorpion both die in the first movie and they're back alive here. What the film doesn't explain is that Sub-Zero is merely a title and the Sub-Zero from the first film was the brother of the one in the second film. Scorpion is infact an undead ninja. Fans of the games on the other hand would most likely know all of this.
 * The film does have a (throw away) line about being the brother of Sub-Zero, and being that the first movie showed Scorpion removing his mask to show a fire-breathing skull him coming back to life isn't sharp leap. Watching the second movie and not the first, however, would still count as a lockout.

Literature

 * The Elder Scrolls Novels are based on the video game series, and if you don't know the continuity and lore then most of the events of the novel will sound like an Ass Pull when it actually does Make Sense In Context.
 * In another example of a creator locking himself out of his own continuity, John Varley, in an introduction to one of his Eight Worlds novels, admits that he's long since lost track of all the background details of the series, and has given up trying to make the later novels fully consistent with the early ones.
 * Terry Pratchett said much the same in the introduction to the first edition of The Discworld Companion. Although he does still make the effort; if necessary consulting with Big Name Fans who actually know more about the Discworld than he does, such as the Companion co-author Stephen Briggs.
 * Pratchett wrote his way out of having to be consistent, all errors are blamed on the fact that even the History Monks can't quite always get time back exactly the way it should be after the magical disruptions that occur.
 * The Wheel of Time series is a dense example of this. As the series progresses, and both the cast and pagecount swell, individual characters get less and less face time. It's sometimes several hundred pages between a character's appearances, even for main characters. Two of the main characters, Mat and Perrin, have even been left out of an ENTIRE book at one point or another. Worse, the characters have often been active in that time, leaving the reader to infer what happened since they were last seen. Not that we're bitter.
 * In fact, it is quite clear that till the 4th book or so, each book provided info from previous books, including character development history and some important pieces of lore. However, by the 5th book, no more "backward compatibility" is provided and the writer assumes that readers have read the previous books.
 * To the point of removing anyone three books or older from the glossary. Readers may have trouble remembering which of the 20 A-named female channelers was Aes Sedai, Rebel Sedai, Aeil, Seachan, or Dark-aligned. They tend to blur together after 10,000 pages or so.
 * And then in the next Doorstopper...
 * Isaac Asimov put the Foundation series on a decades-long hiatus in the 1950s in no small part because he found it tedious to work a synopsis of the previous stories in so that new readers would know what was going on. He also got fed up with having to reread the material himself to keep it consistent, not that it did him much good. A fan later handed him a long list of inconsistencies within the 'Foundation'' stories.
 * Attempting to get into George R.R. Martin's A Song of Ice and Fire involves going through five (eventually, seven) Doorstopper novels, each with so much continuity that it's no wonder the man is taking ages to continue the series. If he creates a plot hole, someone's going to try to call him on it before the book gets to the editor.
 * Interestingly, the author later wrote two prequel novellas (with a third on its way), starting with The Hedge Knight which essentially reproduced the Ice and Fire themes about power and politics down to a much smaller and far easier-to-digest form, and radically less intimidating to newcomers, particularly the graphic novel adaptations.
 * Also interesting to see how the apparently very faithful HBO TV adaptation Game of Thrones (currently in production) handles the uber-serialised, densely-plotted structure and the vast cast of characters in the story.
 * Answer: basically the same. The plot is reproduced quite faithfully and getting lost is easy. Having said that, the TV series benefits from the presence of ""Previously On..."" intros. They only cover what happened in the episode just prior to this one, but it still helps. (Also, it seriously helps to have faces and voices to hang onto character names. Even some characters who were Scrappies in the books are getting a better reception on screen.)
 * Stephen King hired author Robin Furth to be his archivist and continuity editor to assist him in writing the final books of The Dark Tower. She compiled an encyclopedia that King referred to during writing that was published itself as Stephen King's The Dark Tower: The Complete Concordance. He says in the foreword to that book that there was no way he could have completed the series without such a document.
 * And sadly, it shows. Many of the books most important plot points are mentioned only in passing, which can result in a whole mess of confusion even for those who have read all the books in order.
 * Perry Rhodan has a real problem with this. With a backstory of over 2500 issues in the main series alone that might become relevant for the current plot at any time and story arcs that last for 50 to 100 issues it can be quite hard for new readers to break into the series.
 * Nowadays they take some pains to make the round numbers a good place to start, without too much pre-knowledge. Also, in each issue there is a small glossar explaining plot-relevant background that a new reader might not know (or an old reader might not remember).
 * Warrior Cats: It is possible, if not a bit difficult, to start reading the second series without reading the first series. However, by the third series, things apparently get nigh incomprehensible for people who haven't read all of the previous books.
 * Katherine Kerr's 15-book Deverry series is divided into four parts; starting at the beginning of any one of the three latter will cause you to only miss half of the significance of what's happening... The Dragon Mage (3rd series) is probably the worst offender, since it tells about the end of the civil war, which has been earlier covered in three other books.
 * To keep up with all the various plots and Loads and Loads of Characters in the Honorverse by David Weber, you not only need to read the mainline titles, but the sub-series and short story collections, which are themselves not in chronological order. Go here for a reading order. The books are mostly free, so it won't set you back much.
 * Eric Flint's 1632-verse is a "shared universe" open to anyone who wants in. In other words, any fan of the series can write their own contributions to it and have them entered into canon. Flint and his co-writers then tend to take characters introduced in these stories and work them into the main series. Thankfully, the short stories that have the most impact on the main story have been collected into their own "Ring of Fire" anthologies.
 * The Harry Potter books partially avoid this trope thanks in large part to the film series, the popularity of Harry Potter in general and some exposition on JK Rowling's part. You can watch the first couple movies, pick up the third book and pretty much get everything. Likewise, if you know the basic story of the first book/movie, you can read the second book without much trouble. After those points, though, it gets kinda muddled.
 * Various Star Wars Expanded Universe works assume the reader has at least basic Broad Strokes knowledge of important EU events and don't even attempt to make sense otherwise. Amazingly, other works still manage to remain accessible, though the knowledge of the movies is still pretty much required.

Live Action TV
"Hurley: Okay. See, we did crash, but it was on this crazy island. And we waited for rescue, and there wasn't any rescue. And there was a, and then there were other people on the island. We called them the Others, and they started attacking us. And we found some hatches, and there was a button you had to push every 108 minutes or... well, I was never really clear on that. But... the Others didn't have anything to do with the hatches. That was . killed them, and now they're trying to kill us. And then we teamed up with because some worse people were coming on a freighter.  sent them to kill us. So we stole their helicopter and we flew it to their freighter, but . And we couldn't go back to the island because, so then we crashed into the ocean, and we floated there for a while until a boat came and picked us up. And by then, there were  of us. That part was true. But the rest of the people... who were on the plane? They're still on that island."
 * The Stargate franchise has been accused of this. A newbie coming it at the eighth season of Stargate SG-1, for instance, is going to need some help understanding who and what all those species are meant to be about. Some people almost gave up after sitting through the pilot episode -- without seeing the movie first. "Who are all these people?!" Somehow it did not occur to the writers that it carried over a whopping six characters from the movie without bothering to give them any proper introduction, in addition to introducing five new major characters in this episode alone. The fact that they moved through Abydos and Chulak in large crowds didn't help. Starting with "Emancipation," when it became obvious that they were focusing on a four-person team, things started to look more manageable.
 * Hence why Stargate Universe features a new cast in a new setting with few links back to the other series (really only cameos) and a different style: to capture new audiences.
 * Babylon 5 freely admitted that it was a "novel on television," and no one starts reading a novel in the middle. J Michael Straczynski said he dislikes the use of "Previously On..." segments, preferring instead to have characters recap the plot with As You Know speeches, which is arguably worse.
 * Many times in the message boards, JMS would say something like "If you've got some friends you've been trying to get into the show, the episodes in the next few weeks aren't too arc-heavy and/or should be able to catch them up on the arc." Which sounds nice at first, until you realize that with most shows, you can jump right in without fear at any point in the season.
 * Most of the jokes on Arrested Development barely make sense unless you have an intimate knowledge of the episodes that have come before (and, in some cases, the ones that come after...). This is why the show developed something of a cult following once it was released on DVD.
 * So bad in The X Files that even a paperback fan book couldn't sum up the mythology of some of the episodes in less than three pages.
 * It doesn't help that the show's continuity is all over the map. Even hard-core fans of the mythology have a rather hard time keeping up with it. You could make a drinking game out of all the plot holes in the mythology, especially in the last two seasons. There is a reason it's called The Chris Carter Effect.
 * Fans of the show are forever locked into a debate as to which episodes are better, specifically the Myth Arc verses the Monster of the Week episodes. They're pretty evenly split between the seasons, with the Arc marketed more to the hardcore fans while the Monsters are marketed to the casual viewer, who is used to not keeping up with the show.
 * The 2000s Battlestar Galactica Reimagined. The series premiere follows immediately from the events of the pilot miniseries, which was not initially included on the Season 1 DVD, and any given episode relies on the viewer being aware of plot details introduced several episodes or seasons earlier.
 * Lost. There's dozens of major and minor characters, all of whom have their own unique and complicated backstories. The fact that these backstories often intersect in unlikely (and often downright implausible) ways makes things even more confusing.
 * They hang a lampshade on it in Season 5, with Hurley explaining why the Oceanic Six lied to his parents in his trademark Buffy Speak:


 * Farscape. The show would have been more successful if this trope hadn't intersected badly with Growing the Beard.
 * According to articles, the network executives cancelled Farscape precisely because of the Continuity Lock Out.
 * Scrubs is fond of minor subplots that develop from episode to episode (Dr. Mickhead killing his wife, "the world's most giant doctor," Crazy Dr. Hooch and Dr. Kelso's family issues stand out), so that if you come across an episode with one of these b-plots, you'll miss a bit if you haven't seen a specific set of episodes before. The major plot points are fairly simple to follow, however.
 * HBO's The Wire. To the point that the first few episodes of each season are blisteringly confusing as you try to sort out all the new characters that you will have to know for the subsequent rest of the year. Just try to start even three episodes into the first season, and you won't understand a thing.
 * It's especially painful for viewers who tried to start watching the show during the later seasons. The Call Back references to past events become especially heavy in the last two seasons, and if you haven't been paying close attention through the entire series, you'll miss key thematic elements like (and even blink-and-you-miss it cameos).
 * Try watching Glee mid-season without the "previously on" segment to clue you in. The pregnancy plot was confusing enough in context. One can only imagine trying to watch an episode that contained that plot without knowing the context.
 * Averted hard in the second season, which can be easily summarized as "a bunch of teenagers doing some random stuff, acting different in every episode for no particular reason. Also, there are choir competitions in three episodes". This was the huge complain why the second season was considered mediocre compared to the first one by most critics. The writers promised to fix this for the third season, however.
 * This trope is often blamed as one of the contributing factors to the cancellation of the original series of Doctor Who - amongst a lot of other issues that the show was facing at the time, the fact that a fairly large portion of the stories broadcast during the 1980s seemed to hinge upon the audience being aware of characters, events and storylines which hadn't been seen for upwards of ten or even twenty years didn't make the show any easier to watch. Matters weren't helped by the fact that this was well before VHS and DVD was prominent enough to allow people to catch up on the old stuff, and that a lot of this old stuff had been deleted from the archives anyway, meaning that even if the technology had existed, the original material didn't.
 * In the new series of Doctor Who, the later into any given series an episode occurs, the lower the likelihood of a casual viewer having any clue who the characters are or what is going on. The most extreme example is the cliffhanger of "Turn Left": the Arc Words from the first series. We are then introduced to nearly every Companion or character who had appeared in multiple stories from the past four years, as well as a few of the main characters from the spin-off shows.
 * David Tennant's final episodes suffered from this as well.
 * Also one of the problems with the TV movie--they'd included enough from the old series without properly explaining it that it wasn't going to make nearly as much sense to anyone unfamiliar with Doctor Who. Given that this was long prior to YouTube and BBC America, most Americans knew little to nothing about it, and while it tossed in all kinds of plot-points from the series it failed to give them nearly enough context.
 * "The Impossible Astronaut"/"Day of the Moon" may leave people baffled as to why, or why the Doctor seems visibly concerned with the word "Silence".
 * Heroes. Good Lord, Heroes. The writers really wanted to give the impression that there were characters with powers everywhere, which is one of the reasons it was so interesting and complex. On the other hand, even viewers who watch every week could be confused with all of the new characters and old characters simply disappearing. Not to mention all of the Face Heel Turns and Heel Face Turns. Just buy the DVDs. It's more comprehensible that way.
 * Angel, from the end of the first season on, became increasingly arc-driven, to the point that season four required that you be familiar with many of the developments of the past two years to grasp the complexity of Jasmine's advance planning. Network execs reacted to this by insisting that season five be much more typical, revamping the entire location of the show and substantially modifying the mission of the main characters.
 * As noted in its Film entry, the Star Trek franchise was reset precisely because of this trope. The original series and Star Trek the Next Generation largely averted this by focusing on "crisis-of-the-week" standalone episodes that could be watched in (almost) any order, without sacrificing narrative. By the time Star Trek Deep Space Nine was knee-deep in the Dominion War arc, you'd have to have watched the prior seasons to understand the main conflict and the various interpersonal conflicts. Star Trek Enterprise also took this trope to an extreme point by having many episodes only serve to tangle up continuity even further by trying to resolve plot holes and conflicting elements from previous series.
 * The "Mirror Universe" episodes in DS9 and Enterprise assume you have knowledge of the MU episodes from the original series (and, in DS9's case, the earlier seasons).
 * A large reason why the Enterprise series finale, "These Are The Voyages", was such a polarizing episode was due to the B-plot (which was a concurrent side-story to the Next Generation seventh-season episode "The Pegasus" - if you've never seen the episode, you're lost as to why Riker is mulling over a decision to tell Picard about his involvement with an illegal Romulan cloaking device).
 * In Treatment really requires the viewer to watch every episode in order, even if you don't like one (or more) characters and want to skip them from week to week. If you do not view every episode, you won't understand what's going on later in the week or in the series.
 * Buffy the Vampire Slayer could be somewhat guilty of this, especially during the fourth season and onwards. The most egregious example comes during "This Year's Girl"/"Who Are You", where Faith re-appears. It's pretty much assumed that the viewer knows this fact, and despite this being lampshaded by newcomer Riley ("Who's Faith"), very little explanation is given, and you'd better be watching the spin-off too, 'cos otherwise you won't see the end of this mini-arc, to understand what the hell to make of Angel's appearance a few episodes later.
 * Interesting is that this trope functions in-universe too. The Scoobies are a very self-contained group with their own in-jokes and insider information that makes getting close to them very difficult and makes miscommunication practically a given.
 * And God help you if you pick up the Season Eight comics after a substantial time away from the show.
 * Lampshaded again in a hilarious, fast-paced exchange between Buffy, Giles, and Principal Wood in season seven while discussing all the things that have happened to Spike.
 * Dollhouse. Joss Whedon loves this trope. This was particularly true of the s2 episode "The Attic": the concept of the Attic had been mentioned only once since the previous season, and there was no explanation of who Mr Dominic is (and he hadn't been seen or mentioned since season 1, either).
 * An early version of The Sarah Jane Adventures story "Secrets Of The Stars" would have featured aliens named the Mandragora who had last apppeared on Doctor Who in the 70s. This was one of the reasons why they were replaced with the Ancient Lights in the final product, the story would have been relying too much on one from around 30 years ago and thus locked out the young target audience.
 * It's possible to watch Seasons 1 & 2 of Ashes to Ashes without first seeing Life On Mars - which introduces you to Gene, Chris, and Ray, and tells Sam Tyler's story - but if you haven't seen LOM by the time A2A hits Season 3, you're almost completely lost. Sam and what may or may not have happened to him play a huge part in
 * Weeds tends to reveal major plot points in the current arc each episode, making it very difficult to get on track if you miss even one episode. And watching an episode in the middle of the season with no previous context will basically make no sense.
 * Smallville, particularly in the final season.
 * The Doctor Who spinoff Torchwood is sometimes reliant on continuity from its parent show, and its writers stubbornly refuse to explain the connections any more than is absolutely necessary.
 * Torchwood's main character, Captain Jack Harkness, is shrouded in mystery. Some of his backstory is revealed on Doctor Who, while some remains hidden. A viewer of Torchwood alone could wait forever for explanations that already happened on another show. The same is true of the Torchwood Institute itself.
 * The Series 1 episode "Cyberwoman" assumes a familiarity with the Doctor Who Series 2 finale episodes for viewers to understand why the villain is so frightening. Without that information, viewers would be baffled by references to recent historical events that bear great significance to the plot.
 * The reason behind Jack's jarring personality shift at the beginning of Series 2 is only vaguely alluded to within the actual series. The viewer would have had to have watched the three-part Doctor Who Series 3 finale to understand where Jack had disappeared to, and why he was suddenly much happier.
 * Ditto for Jack's brief cameo in the Doctor Who special "The End of Time". You would have had to have seen Torchwood: Children of Earth to understand why he was drinking away his sorrows on a space freighter rather than fighting aliens in Cardiff.
 * Hong Kong or Taiwan serials can stretch for hundreds of episodes and rarely pause to recap who's who.
 * Supernatural, especially since season four, when the angels started getting involved. Considering the show's high HSQ, watching a newer episode without following the story makes for bizarre and incoherent viewing.
 * Take season 4, episode 16: So, the guy torturing that dude who looks like a paedophile is the good guy? And what the hell are the angels stabbing each other over?"
 * Fringe avoided this problem during seasons one and two, thanks to its heavier focus on self-contained Monster of the Week plots, with the occasional Wham! Episode for the longtime fans. According to JJ Abrams and the other Fringe producers, they specifically wanted to make the show more accessible and avoid the impenetrable-for-newbies style progression that Lost did. However, by the time season three came around, the plot became too tough for new viewers to follow, so the show's structure became far less episodic. It's understandable though, as the more procedural feel of the first two seasons would have watered down the major plot developments (with many of them reaching Mind Screw territory) that season three unraveled.
 * Around 20-25% of How I Met Your Mother is comprised of flashbacks -- not just distant flashbacks to the characters' youth, but flashbacks that occurred during the show's run, during distinct canonical periods of the show's run, and even precise episodes or even scenes of the show's run -- and is full to the brim with running gags, in-jokes, huge quantities of detailed backstory, and plot elements and assumptions that are rarely if ever lampshaded and utterly inexplicable if you haven't seen the previous (or sometimes, like Arrested Development above, even future) episodes (or flashbacks, or flashforwards) that explain them. The only reason the show isn't the most insular and locked-out show ever broadcast is because of Future!Ted's narration, which reminds viewers of events or situations relevant to the episode at hand and often recaps essential plot points with a quick "Kids, remember how I told you about..." so that at least the plots make sense, even if many of the jokes and character reactions will leave new viewers scratching their heads in bewilderment.
 * "Mad Men" suffers from this in spades. The episodes are generally not self-contained, and most of the subtext is built upon episodes from previous seasons. The problem is that this series built on subtext. Viewers must watch from the absolute, S 1 E 1 beginning. The "Previously On..." segments absolutely do not help.

Newspaper Comics

 * Nearly every Newspaper Comic in existence is written under the belief that not everyone gets the newspaper every day, so most of them are of a Gag-a-Day format to avoid this. However...
 * Both Floyd Gottfredson's Mickey Mouse daily strips and Ward Greene's Scamp daily strips began as essentially one continuous story, but both eventually shifted to gag a day formats.
 * That also makes them particularly tricky to separate into individual stories for reprinting in comic book form (besides the obvious fact that they have to make up a meaningful name for the story arcs), for example, Gottfredson's Mickey Mouse as the Monarch of Medioka (Printed in WDC #593-599 starts of with a conversation referring to the immediately preceding adventure, and the plot is set in motion by spending of the money they made off of said adventure. The preceding story, In Search of Jungle Treasure was printed in issues 4 and 5, so unless you have a complete collection, you pretty much have to take their word for it.
 * Modern newspaper strips with running plots generally get around this by decompressing the plot so much that every minor detail happens over at least 3 days. Of course, this also means you have to read several months' worth of strips to get anything meaningful out of it.
 * Fleep was an Ontological Mystery, so the entire story was progressed through clues slowly gained over the various strips. It was canceled for being too confusing.
 * Candorville is doing its best to avert this, sometimes filling an entire panel with As You Know dialogue, but it's been steadily failing ever since it started introducing monsters and prophecies. Now there are at least two factions, maybe three, trying to Take Over the World, and a new reader may not initially realize that any of them are present.
 * Bloom County hangs a lampshade on the concept in this strip.
 * Doonesbury is a victim of this. 40 years of strips with close to 100 characters, around 30 or so who appear on a regular basis.

Other

 * Bionicle has definitely became an example of this trope, especially after the introduction of the on-line serials. The main story arcs tended to avoid this, but when former main characters that had been cast aside for years got back on stage, even that went messy. The whole storyline basically balanced on a thin line between trying to please the older fans and bring in fresh blood. Probably one of the main reasons LEGO decided to cancel the line and bring in Hero Factory, which is much lighter on the story.

Professional Wrestling

 * Usually avoided in pro wrestling, since most of the characters (at least if the fall between the two extremes of "irrelevant" and "universally popular") will switch from Heel to Face and back again (or vice versa) quite a few times over the course of their part in an overall story arc, with other characters all but forgetting about the bad deeds they committed as Heels or the good deeds they committed as Faces (unless, of course, a character is explicitly confronted with his/her past). However, since World Wrestling Entertainment has a video archive going back to the 1960s and everything (or almost everything) that occurred within those 40-plus years is regarded as canon, it often becomes helpful to play vintage video clips in the montages in order to bring everyone up to speed.

Video Games

 * Metal Gear slowly rose from humble origins, into the self-sequels Metal Gear Solid and Metal Gear Solid 2, had a brief blip for the stand-alone Metal Gear Solid 3, and then gunned the canon whole-heartedly into the massive continuity snarl-ups of Metal Gear Solid Portable Ops and Metal Gear Solid 4, both of which only a very serious and dedicated fan would be able to understand totally.
 * As a sort of alternative, the Ac!d games happened in an alternate universe, but they still expected a familiarity with the main phase series with its spoilerrific character cards. In the first game's story, a lot of hints about Snake's identity and motivations require some knowledge of his main phase Canon Backstory, such as his sterility.
 * Metal Gear Solid 3 is an interesting exception in that while the story can be completely enjoyed and understood on it's own it's packed with Continuity Nods and back story for characters in the other games.
 * Some games or companies attempt to keep world bibles in order to allow their development teams to keep track of what is what in a setting. It works... sometimes.
 * World of Warcraft is like this at times. Events happen outside the game's continuity that still affect the game. Why is the king of Stormwind back for Wrath of the Lich King, and where was he? Why is  dead in Cataclysm? Op, better read the expanded universe material to find out!
 * To be fair, the games never leave you completely out of the loop, but you might have to dig for those tidbits. And even then it's just the basics, not the complete story.
 * Blackwing Descent, one of the tier 11 raids, is home to Deathwing's son Nefarian, who is running experiments on different kinds of dragons. Except Nefarian was already killed several years prior to the Cataclysm expansion. Playing through the game alone, you'll never find out how Nefarian came Back From the Dead, what the purpose of his experiments was, or how they tied into Deathwing's plan since the raid doesn't address it and neither Nefarian nor his experiments ever appear or are mentioned outside of Blackwing Descent. Were it not for the Expanded Universe, the entire raid would be a Big Lipped Alligator Moment.
 * Star Craft 2 is also slightly guilty of this. There are summaries on the website, but otherwise you have to read the novels to know anything about Valerian, Tychus, Matt Horner and Nova.
 * The Kingdom Hearts series. Starting from any game from Chain of Memories and onward will get confusing.
 * And to make things worse, the continuity is spread over multiple handheld systems, including the GBA, DS, PSP, and the 3DS. Note that three out of four of these are Nintendo systems. The PS 2 remake of Chain of Memories alleviates the confusion slightly for those without Nintendo handhelds, but they'll need to get a 3DS to get Dream Drop Distance, which will tie together the previous three hand-held installments (358/2 Days, Birth by Sleep and coded) and the inevitable Kingdom Hearts 3. Likewise, those with Nintendo handhelds, but no PS 2 or PSP... you get the picture.
 * Basically, Crack is Cheaper than playing the entire series.
 * It also doesn't help that the Final Mixes in the series are unavailable outside Japan, despite containing critical plot points. This makes it difficult to follow the already complex plot of the series, unless you look up fan translations.
 * Averted in Kingdom Hearts 3D, for the first time in the series, thanks to the recap-like "Memoirs" feature.
 * Strangely averted by Zelda, despite having a humongous Continuity Snarl of a timeline. For example, one can play both The Legend of Zelda Twilight Princess and The Legend of Zelda the Wind Waker without ever needing the knowledge that they are set in two parallel timelines created by Link's time travel in The Legend of Zelda Ocarina of Time, though both games do have plenty of Continuity Nods to their predecessor. This is all because the sequels are isolated, so it the overarching plot between the games doesn't really matter.
 * In the case of direct sequels (like The Legend of Zelda Phantom Hourglass is to The Legend of Zelda the Wind Waker, for example), you get a summary of the events from the last game (and even then, the information isn't really needed, as the new adventures always take place somewhere different).
 * The Ace Attorney goes out of its way to avoid this, to the point of characters avoiding references to other games even when it would make sense to do so. See: Miles Edgeworth in Investigations constantly mentioning that he no longer follows the von Karma way without mentioning the fact that  You would think that would be a big deal.
 * Said series somehow manages to play this trope straight at the same time, as many character appearances and associated in-jokes will doubtless leave many new players scratching their heads.
 * Continuity in The Elder Scrolls games works in a similar way to avert lockout. You don't NEED to know about the Warp in the West to play and enjoy Morrowind--but if you'd LIKE to know how the previous game's multiple endings were resolved, just read the in-game book about it! Of course, business and technical challenges sometimes force some bizarre contortions of continuity, but that's another trope.
 * Melty Blood assumes you already know all the characters and their relationships to each other. If you're completely unfamiliar with Tsukihime, it feels like a massive In Joke.
 * Higurashi no Naku Koro Ni. Theoretically you can jump in about once every four or five episodes and understand what's going on immediately, but eventually you're going to have to review everything you missed anyway.
 * The Legacy of Kain series is hard enough to follow even if you play them all. If you missed one, you have no chance.
 * You'll probably be alright if you miss Blood Omen 2. It gives some back story for the Hylden, but nothing terribly important that can't be gleaned from Soul Reaver 2.
 * Halo Reach is well-made enough that the gameplay is easy to enjoy. Try following the story without having already gone through the EU material, though.
 * Some found the story very easy to follow and perhaps even easier if you hadn't read the EU. There's a team of Super Soldiers, they fight Scary Dogmatic Aliens,, etc. Anyone who had read the EU had to contend with the game's Broad Strokes and multiple retcons. IGN in particular praised this, calling it the most accessible Halo game yet. Halo 3 and ODST, however, definitely fall into this.
 * Arguably the entire fighting genre, not in the story but in game structure. Even most of its fans know that the games can oftentimes get too convoluted for beginners to start playing. This isn't even getting into the terminology, which are hundreds of words and phrases long and many prominent series have adopted.
 * Masahiro Sakurai created the Super Smash Bros series in defiance of this. However, more dedicated players learned how to exploit the physics of the original and Melee to make it as complex as other fighting games, and Sakurai responded by reworking the physics in Brawl.
 * Oh, the stories have got their fair share of it, too. You try to get into the King of Fighters plot without hours of SNK wikiing about why Iori is so pissed off, why that flamboyant guy with the green fire is such a big deal and what the whole NESTS debacle is about.
 * Also, try getting into the plot of Mortal Kombat. Just try!
 * Happened with Mass Effect 2 when it was ported to the Playstation 3. Because of licensing issues, the first game never made it to that console. People were worried that new players wouldn't get the whole story, so Bio Ware created an interactive comic that, admittedly, tells the story from a somewhat awkward perspective. It glosses over Feros completely, leaving some players in the dark about Shiala, the Feros colony, et. all. Even worse, as Admiral Hackett doesn't appear in the sequel outside of passing mentions and a letter, his significance in the recent Arrival DLC is completely lost on players who didn't experience the first game.
 * According to Bio Ware, Mass Effect 3 will subvert this, being "the best jumping-on point" for the series.
 * Anyone playing Super Robot Wars OG Saga: Endless Frontier EXCEED would be left confused if they did not first play Super Robot Wars Original Generation Gaiden, as two characters in the playable cast who were supposedly Killed Off for Real in the main series winds up in the spin-off series. In fact, the developers make it a point you have to play the previous games occuring in the main continuity to know what's remotely going on if you decide to start somewhere in the middle.
 * Playing a Lego Adaptation Game, apart from Lego Batman (which is a semi-original story), make very little sense if you haven't seen/read the source material they are based on, as this blog demonstrates.
 * Metroid Other M is frequently accused of this. While most of the references make sense to a casual fan, the use of this trope pretty much single-handedly turned the Ridley scene into one of the most despised scenes in the series history.
 * To give you an idea, this plot point came from an obscure manga that was never released outside of Japan, where Samus has already feared Ridley since he killed her mother and lead a massacre of her home planet K2L. About the only indication people get is a nonsensical shot of Samus turning into her child self, rather than actually showing the ravaging of K2L for context.
 * Considering this is, AT LEAST, the Fourth Time she has Met Ridley, and she ALREADY killed him two times over...and that's not even COUNTING the Prime Series and other spin-offs. It still makes no goddamn sense. She should be yelling about "WHY DO YOU NOT DIE!" instead of cowering like a Little Girl. Literally.

Web Animation

 * Homestar Runner. It's not a very continuity-heavy site really. But there is large reliance on in-jokes and running gags. The toons are sorted in to different categories so you're not even sure where to start. However, it has a wiki that is so helpful and comprehensive... it's a little scary.
 * This is basically the only place you'll find a chronological list of the toons and games.

Webcomics
"This link is the in-comic recap of the first year."
 * Sluggy Freelance. Trying to understand the significance of things without going through an Archive Binge... just doesn't work. Sluggy Freelance may be the only webcomic where the creator forgot his keys and locked himself out of his own continuity. In his defense, the writer has become aware of this trope and provides relevant links at the bottom of the strip for anyone who hasn't gone through the eight plus years of continuity.
 * To its credit, it does have a lot of humorously-framed recap strips in which characters rant about important past events while other characters Lampshade the exposition. Eventually however, the continuity became so long and tangled that in-comic narration wouldn't cut it anymore (and in Sluggy Freelance, an Archive Binge — or even an Archive Trawl — will take weeks unless you read for several hours a day.)
 * Megatokyo. If you haven't read it from the beginning, you can forget about understanding the story. This is largely due to its character driven nature. If you haven't witnessed every second of Piro and Kimiko's courtship, or taken notes on each tiny nuance of the Piro/Miho dynamic, you aren't going to have any clue what's going on. Even then you might still have trouble, but that's another trope entirely
 * Dominic Deegan, making the sheer dedication of the Hatedom all the more puzzling.
 * Hate is as strong an attracting force as love. See the Fallout fandom, who hate every single thing about the series but will tear you apart if you try to take it from them.
 * Penny and Aggie is a tapestry of numerous characters and subplots and overarching plots and rivalries...just read it from the beginning and you'll understand it better. The website now attempts to help those not planning on an Archive Binge by displaying a summary of the current plotline and the characters involved. The reader is still missing out on a wealth of backstory and characterization if they rely on that alone.
 * Scary Go Round was brought to an end due, in part, to its massive archive keeping new readers at bay. The following strip Bad Machinery is set in the same world, but with new characters (besides two supporting characters.)
 * There are forgiveable elements of this in SGR's first strips, too. Ryan, Shelley and Fallon drop in with little introduction because they were already established in the predecessor strip Bobbins.
 * Of course, there are various characters still around from SGR, too, it's just that their backstory is no longer needed to understand their current role. (Including at least one who logically shouldn't be able to come back.)
 * Girl Genius has so many characters who can be summarized as "Mad Scientist", many of whom disappeared for several years and then resurfaced, that even after reading the entire archive it's hard to keep track of what's going on now.
 * What's going on? SCIENCE!, that's what's going on.
 * Any MSPaint Adventure, but particularly Problem Sleuth. Even people who have read every single page in order occasionally need to sit back and think "Wait, what the hell is going on?" If you have a good grip of the story, even skipping a few pages will mean you won't understand a Call Back or five.
 * Generally, webcomics having call backs isn't so rough because of their archives, but MSPA is one of the few webcomics (except, perhaps, the Walkyverse) that requires you to read unrelated webcomics to get all the jokes. Want to understand why Jade is making jokes about pumpkins in Homestuck? What's up with Ace Dick's extended sideplot in the Game Of Life? Well you had better read every badly-drawn, nonsensical corner of Jailbreak!
 * Note that the author acknowledged the need for think-time during Problem Sleuth by having not one, not two, but three recap comics throughout its run.
 * Homestuck, Problem Sleuth's successor, has a very very very very very convoluted plot. One can spend hours trying to fit all the pieces together, and chances are that you've probably still missed something that the fandom hasn't. And then there's the tangentially related pages such as the Midnight Crew and Sweet Bro and Hella Jeff, which somehow weave through and permeate the entire plot even though they're in rather... inaccessible locations.


 * Order of the Stick is not quite long enough to invoke this yet, but it's well on its way there, as any strip past the 300-strip mark has a 80% chance of making no sense whatsoever to anyone who hasn't read through the whole archive. It's exactly like joining a RPG campaign in the middle: you'll still get the gamer jokes, but who the heck are all of these NPCs?
 * The Walkyverse tends to avert this. While there is a continuity, starting with Shortpacked won't lock you out of the continuity (you'll just miss some of the references to the other comics, which aren't really important to the plot).
 * The newest comic, Dumbing of Age, completely averts this. While it contains characters from the other comics, it takes place seperate from the other comics. As such, knowing who these characters are means very little.
 * Occasionally there are Arthur King of Time and Space strips that don't make sense unless you know the running gags and continuity points. As with many meta-concepts in AKOTAS, Lampshaded via Arthur's webcomic.

Web Original

 * Given the vagueness of the plot and the fact that all the episodes are online, Lonely Girl 15 would probably not be an example of this, if it wasn't for the tendency of seemingly irrelevant, blink-and-you'll-miss-it background details to become crucial Chekhov's Guns several hundred episodes later.
 * Happens in Survival of the Fittest a great deal. Sometimes, even starting at the beginning of the current version/season isn't enough - references will be made to scenes or characters in previous versions. It's often very bewildering for people seeing the RP for the first time.
 * Arguable with the Whateley Universe, since it now consists of over a hundred stories, most of them novel or novella length. Every major protagonist has a backstory, and girls of Team Kimba all have Backstory novels. Diving in with current stories means you may not get the in-jokes, or the references to prior stories, or what's going on with recurring characters, or some of the ongoing plotlines, like Ayla's blackmailer or Jade's quest, or the people who may be after Toni. Not to mention that it's assumed that you already know what the main characters' powers are.
 * Also arguable, That Guy With the Glasses, especially with how many multi-video running gags, crossovers, story arcs, and callbacks to past videos they use. Most hardcore fans of the site were lucky to find the The Nostalgia Critic's stuff on YouTube before it grew into an entire critic community, so they have a leg up on knowing each Running Gag. Watching individual reviews on the site, it seems fairly accessible, but understanding something like Kickassia is impossible unless you have a good understanding of the group's dynamic, not to mention the use of past characters.
 * Linkara is definitely one of the worst with his ongoing story arc, but to his credit, he recently posted on his own website every arc-related episode in chronological order. There's also a more recent recap video.
 * Suburban Knights was specifically written to avoid this, however. You'll definitely get more out of it if you're a fan of the site (especially regarding the use of Ma-Ti) but the story is perfectly comprehensible to someone coming in cold.
 * Ostensibly, one of the reasons Rooster Teeth ended Red vs. Blue: The Blood Gulch Chronicles at Episode 100 was to prevent Continuity Lock Out. While they succeeded, the series from that point forth became much more plot based, and a good number of the Call Backs still require familiarity with all the older episodes (as opposed to just episodes from the most recent trilogy, Recollection).
 * The Slender Man Mythos is slowly becoming this, particularly Everyman HYBRID with its Alternate Reality Game elements and the miscellaneous Core Theory blogs. Aggravated by the occasional Dead Link.

Western Animation
"Homer:"
 * One of the many complaints people had about Beast Wars is that when it aired, it had the strongest continuity ever seen in a cartoon on American or Canadian TV. As a result, a new viewer jumping in partway through is going to be quite perplexed by what's all going on. Then its sequel Beast Machines one-upped it.
 * Ironic with Beast Machines, since they were originally trying to avert this trope by ignoring most of Beast Wars, only to end up with a stronger version of the trope in its own series.
 * Later episodes of The Simpsons suffer from a mild case of this condition at times (though it's understandable for a series in its 23rd season). One particular gag involved Homer (accurately) daydreaming about a "think-tank", a joke which is probably much, much funnier to longtime viewers than new ones.


 * Many of The Simpsons' minor characters are completely bizarre without context, yet the show basically takes it for granted that the audience can recognize and appreciate most of them without any sort of perfunctory introduction or explanation. Examples would include Bumblebee Man, Sideshow Mel, Duff Man, the Sea Captain, or Disco Stu, or even Krusty, all of whom are basically long-running continuations of one-off gags from many, many years past.
 * This is Lampshaded when Marge gets amnesia one episode. She finds all the side characters confusing and creepy and is incredibly disturbed when Homer says they're his and Marge's close friends.
 * Phineas and Ferb might have a bit of this, given how much of its humor relies on Continuity Nods and playing with their usual formula. Still, this affects plot less than gags.
 * There's at least one episode of Codename Kids Next Door that just starts off with the KND trying to steal the birthday cake of the Delightful Children From Down The Lane with no explanation for a new viewer as to why exactly the DCFDTL are supposed to deserve this.
 * ThunderCats (2011) is heavy on its Heroic Fantasy plot, but this makes it fairly difficult to leap in halfway and know what's going on. Some episodes don't really end as much as they just stop, only to pick up right where they left off the next week, which lends to the show being more accessible in large chunks.