As a series progresses, it has a lot of events in it which are supposed to be happening for the first time. Once you do more of the series, you can have characters who have met before meet again, or you can revisit old locations or plots, or whatever.
But if you're doing a prequel, the temptation is to write the same way, by using elements of the series that are familiar to you and your audience. This means using varying degrees of Retcon to say that the "first" appearance of someone or something wasn't really the first, so that you can use it in the prequel. In extreme cases this can lead to a Continuity Snarl where most of a story's cast, antagonists, abilities, etc. all showed up before the main story even began.
Sometimes the pre-first first appearance gets explained away by giving characters amnesia or otherwise effectively wiping out the event, which can itself get weird if it happens lots of times.
A variation may be seen when Time Travel gets involved, and characters meet people in the past who aren't supposed to know them until later. This can be solved either by Laser-Guided Amnesia, or by having the other characters not recognize the time traveler (because he/she either has changed his/her appearance or meets them so far in the past that they've forgotten it by the time they meet in the present).
- According to the Pokémon 4Ever movie, Professor Oak first met Ash, Misty, Brock AND Team Rocket 40 years previously when Oak was brought forward in time by Celebi. Of course, none of the main cast make the connection due to age differences. But you'd think he would have mentioned it at some point.
- They knew Young!Oak by first name (Sam), and his notebook's similarity to the Pokédex is commented on. However, given the time travel thing, you'd think the penny would drop after Oak mentions Sam's name before Ash mentions it.
- 4Kids actually went out of their way to make it completely and utterly obvious that Professor Oak = Sammy, to the point where there were extra scenes added solely for the dub. The original was much more subtle in that it was basically one scene during the credits, specially the scene where Tracy pulls out Oak's sketch book and sees the drawing Sam was doing earlier in the film.
- It makes more sense in the original (sorta), where Sammy was shown returning home to Towa believing that his experience in the future was a dream. In fact, the only clue for the Japanese audience that Sammy was actually a young Professor Oak was during the credits when Tracey finds Sam's faded sketch of Celebi and Pikachu sleeping among Professor Oak's belongings. Although he should still have realized the truth upon examining his sketchbook anyway... or at least shown some surprise upon meeting the kids from his dream from 40 years earlier IRL.
- The 2002 television special Lupin III: Episode 0: First Contact tells the story of how all the main characters met, all at the same time. This contradicts previous origin stories that showed Lupin and Jigen being old friends, then meeting Fujiko, and then meeting Goemon much later. However, the whole thing is told through the Framing Device of Jigen being interviewed by a news reporter, and it's never confirmed that the events of the movie really happened. Especially as a second Jigen shows up to reveal that the first Jigen is actually Lupin in disguise, and probably lying about everything.
- Goblin Slayer: Year One has Goblin Slayer meeting both Chosen Heroine and Priestess. Of course since he always wears his helmet and they've grown a lot since then, it's understandable why they wouldn't recognize each other the first time they meet in the main series.
- Back in the Silver Age, the Superboy series pioneered this, with just about everything from Superman showing up "first" in Superboy, including Lex Luthor being a former childhood frenemy.
- It also provided at least one serviceable subversion, creating Lana Lang to stand in for Lois Lane rather than importing Lois into his childhood. She even became fleshed out into her own character. Pete Ross arguably was a stand in for Jimmy Olsen and even he took on his own life (being Superboy's first Secret Keeper aside from his parents, both from an in-continuity and real world perspective.) Although in the end, Superboy met both Teenage Lois and Infant Jimmy anyway.
- He also met Aquaman (called Aquaboy), Bruce Wayne and Oliver Queen back when they were all teenagers.
- He even met his cousin Kara, the future Supergirl, during an incident where he accidentally ended up on Argo. The fact that he didn't recognize her when she arrived on Earth years later was explained to be the result of Laser-Guided Amnesia.
- It reaches really ridiculous levels in the standalone graphic novel Superman: Blood of My Ancestors, where we learn that that Kal-El wasn't even the first person in his family to become a super-powered crusader. Apparently, in Krypton's distant past, Kal-El's ancestor "El" developed suspiciously Superman-like powers after dying and being resurrected by the god Rao, going on to become a revered messiah (complete with a rudimentary "S" symbol painted on his chest) and fight an evil bald warlord named "Utor" before being brought down by his weakness to Kryptonite. So...even though Superman's powers are supposed to come from exposure to Earth's sun, they really just run in the family.
- This sort of silliness isn't confined to the Silver Age, either. One Modern Age story in World's Finest shows Jor-El scouting out possible planets to rocket baby Kal off to with a sort of ultra-3D Subspace Ansible. Which lucky Earthling does he chat with to see if the human race might be up to the task of raising the Last Son of Krypton? Why, Thomas Wayne, of course.
- As the G.I. Joe comics progressed, it ended up that Snake-Eyes had met practically everyone else in the franchise prior to joining the Joes, from fellow Joes Stalker and General Hawk to the villains Cobra Commander (whose brother was responsible for the death of his family), Destro, Baroness and Storm Shadow.
- As a child, Storm stole Charles Xavier's wallet while he was in Egypt to confront the Shadow King. She also met and spent some time with T'Challa back when the two were teenagers.
- Apocalypse from X-Men was later revealed to have encountered, over the course of his long life, the following characters from different corners of the Marvel Universe: Mister Sinister, the Externals, Thor, The Eternals, Kang The Conqueror, the Brood, an ancient avatar of Khonshu, Abraham van Helsing, Jonathan Harker and Dracula.
- According to The Invaders, Thor once fought against Captain America, Namor and the rest of the team during World War 2 after having been summoned to Earth by Hitler. A young Victor Von Doom was also present during this storyline, but never directly interacted with the heroes.note After realizing he'd been manipulated by the Nazis, Thor realized he was not yet meant to walk among humans, and returned to Asgard. A throwaway line hinting at Laser-Guided Amnesia explained why Cap and Namor never mentioned knowing Thor when they served together on the Avengers decades later.
- Jason Aaron's Avengers run revealed that as a young man, Thor's father Odin was part of a team of proto-Avengers that included Agamotto (the first Sorcerer Supreme), and prehistoric versions of Black Panther, Ghost Rider, Phoenix, Iron Fist and Starbrand. Upon meeting T'Challa in the present for the first time, Odin claimed to have met many different Black Panthers throughout history.
- Wolverine was later retconned to have meet loads of different characters in the past, including Captain America, Peter Parker's parents, Carol Danvers, Black Widow, Mystique, Nick Fury, The Incredible Hercules, Daredevil enemy Nuke and even Charles Xavier and Magneto back when they were young men. And that's not to mention basically everybody ever tied to Weapon X. In fact, the revelation about Weapon Plus does this to Weapon X, revealing its ties to Nuke and Project: Rebirth, that created Captain America.
- Mega Man does this with a lot of Robot Masters; before the plot of Mega Man 3, Pharaoh Man, Bright Man, Plant Man, Concrete Man, and Splash Woman had all made significant appearances, and a number of others had made cameos. And due to placing the events of Super Adventure Rockman between 2 and 3, the Robot Masters from the latter were all well-established characters by then as well. That said, these were all preexisting Robot Masters in the games that Wily simply reprogrammed and repurposed, so it makes sense that they were at least around for a while prior to their games (hell, Mega Man recognized the crew from 9 on sight as Doctor Light's creations, and they're noted to be very old). One case where this notably wasn't done was with the cast of 5, 7, and 8, which were all explicitly created by Doctor Wily for the events of those games and therefore would have no reason to exist beforehand.
- In the movie Young Sherlock Holmes, not only do Holmes and Watson know each other in boarding school as young teens rather than meeting as adults as happens in the books, but in a short post-credits scene it's revealed that Moriarty's enmity towards Sherlock Holmes goes much further back than the books indicate: he was a junior master at the school that both Holmes and Watson went to, and the mastermind of the first case Holmes ever solved. Lestrade also plays a part.
- The writer also interestingly makes Holmes and Watson the same age. From internal evidence in other stories in the Holmes canon, Holmes in A Study in Scarlet is 27 and Watson 31, so not likely to be bunkmates.
- Lampshaded during the credits, where the fimmakers admit the whole thing was a "what if?" scenario
- We were expecting Anakin to have met Obi-Wan and Yoda in the Star Wars prequels. Not so much C-3PO and R2-D2.
- C-3PO had his memory wiped at the end of Episode three. Necessary, because it explains the otherwise awkward complete lack of scenes in A New Hope where C-3PO says something along the lines of "Skywalker and Kenobi, huh? You know, it's funny ..." We can kind of explain Obi-Wan not recognizing the droids as a case of "You all look alike to me." It's perhaps a bit odder that he doesn't recognize them even after learning their names, but R2-D2 is referred to several times as "an R2 unit" as if it were a model number, so apparently his "name" is just "D2" (presumably a shortened version of some longer serial number). There are only about 1300 possible two alphanumeric character combinations so it's likely there are a lot of R2-D2s rolling about the galaxy.
- Downplayed to the point of being Played for Laughs in X-Men: First Class: turns out Magneto and Xavier met Wolverine decades before the first movie... but their meeting was so brief ("Go fuck yourselves.") that none of them remember it (and Wolverine wouldn't remember it anyway because of his amnesia).
- In Days of Future Past, however, Xavier does remember Wolverine (if Magneto does too, he shows no sign of it).
- Dragonlance is like this. You have the Chronicles, then the Twins trilogy, and then they start filling in every character's backstory, usually featuring one or more characters from the chronologically later canon. Considering that the characters were supposedly no more than fourth level or so when they started the 1st Edition AD&D module, Dragons of Hope, the likelihood of them having that many glamorous adventures together is... pretty small.
- Artemis Fowl did the Time Travel version in The Time Paradox. Artemis and Holly go back in time and meet a past Artemis and Butler. The past versions eventually have their memories wiped, but it's implied that Artemis' residual memories of the meeting spark his interest in fairies, leading to the events of the first book.
- This happens quite a bit in the Redwall book series, both for the characters and for the history of Mossflower, Salamandastron, and the Abbey itself. There's eight books set chronologically before the first one that was published, which leads to quite the bit of Continuity Snarl. This might explain Jacques' later focus on books set after Redwall chronologically, as it gave him more room to work with.
- The worst offender is Martin the Warrior, an entire book is devoted to Martin's adventures before he came to Mossflower, despite the fact it had already been firmly established what his backstory was. The Legend of Luke turned this Up to Eleven as a single one paragraph story of what happened to Martin's father became an entire Shoot The Shaggy Dog Story.
- Derek Robinson uses this a lot in his serial novels of wartime aviation. Characters in one novel frequently carry over into the next - providing they survive. In Hullo Russia, Goodbye England, several characters carry over from the last of his WW2 trilogy, Damn Good Show as we follow 409 Squadron into the nuclear jet age. As a bonus, intelligence officer Skull Skelton returns into an age where his moral ambiguities and ability to see in terms of finely nuanced greys are welcomed by an RAF to whom the old certainties are dead.
- The Star Trek novel Enterprise: The First Adventure has most of Kirk's Enterprise crew already meeting each other before the start of the original series.
- Smallville has had appearances (sometimes even as regulars) of Lex Luthor, Brainiac, General Zod, Bizarro, Toyman, an In Name Only version of Mxyzptlk, Doomsday, Darkseid, Supergirl, Lois Lane, Jimmy Olsen, the Daily Planet, the Fortress of Solitude, the Phantom Zone, Green Arrow, Black Canary, Aquaman, Cyborg, Impulse, and pretty much everything else associated with Superman even though the entire premise of the series is about Clark's life before being Superman. Suffice to say, the pretense of being a prequel to the Superman mythos was dropped some time ago.
- Similarly, Gotham features the Penguin, the Riddler, the Joker, the Scarecrow, Poison Ivy, Mr. Freeze, Firefly, Bane, Mad Hatter, Clayface, Ra's al Ghul, Hugo Strange, Professor Pyg, Azrael, Solomon Grundy and even obscure characters like Electrocutioner and Magpie all operating as active supervillains a decade before Bruce Wayne becomes Batman.
- Star Trek: The Original Series: James Kirk was the "first person" to do lots of stuff. But it turns out Jonathan Archer (captain of Star Trek: Enterprise) did them all firster.
- Archer also encountered the Borg nearly two centuries before Star Trek: The Next Generation. The writers had to take great pains try to show why none of this knowledge would survive into the TNG era when it would have been extremely useful.
- Although that being said, it does lay to rest a minor Fridge Logic issue how Lieutenant Commander Shelby from "The Best of Both Worlds" could have been Starfleet's "foremost expert on the Borg" (implying that they had more than one Borg expert) when Starfleet had only encountered them once, and when Shelby hadn't even been on the Enterprise-D when it happened.
- Ditto for the Ferengi. The name itself is uttered early in the first season, but even T'Pol hasn't heard of them at that point. Later, a group of them hijack the Enterprise... but they never once name their species, and no one thinks to ask. All of this is seemingly designed to maintain the continuity.
- Babylon 5: The prequel TV movie establishes that John Sheridan had already met and been on a mission with Dr Stephen Franklin during the Minbari War, some twelve or thirteen years before Sheridan became Franklin's commanding officer. Admittedly a very mild exampleit's not that far-fetched for an officer and a medic to meet during the Gulf War and then have the officer, now a colonel, assume command of the medic's unit during the Iraq War.
- It becomes less mild when you consider that G'Kar was also with them on the mission, that they got bombed on Londo's orders, and that as a result they were captured and met Delenn.
- Somewhat justifiable that Sheridan and Franklin didn't recognise Delenn, since they weren't in the best condition at the time, and Delenn looked very different when Sheridan met her again, and Londo had good reason to keep his mouth shut, and Delenn keeps secrets so much it's probably habitual by this point, but you'd expect Sheridan to recognise G'Kar.
- It becomes even less mild when you consider that the only thing saving Franklin's (and Sheridan's) life was the Minbari word Isil'zha (i.e. "the future"). One would assume this word's burned into one's mind for the rest of his life. When Marcus showed Franklin the ranger badge, Franklin had seemingly never heard the word.
- Happened a lot on Friends, thanks to the various flashback episodes the show featured during its ten year run. Notiecably Chandler was originally just Monica's neighbour but early on the writers expanded on this so he was Ross's college roomate, met Monica and Rachel while they were in high school and spent frequent Thanksgivings with the Gellers, to the extent that he was the cause of Monica's weight loss and she contributed to his hatred of Thanksgiving. The writers stated that he became Monica's neighbour because, now as close friends, she tipped him off about the avaliable apartment across from her.
- As did Felix and Oscar of The Odd Couple (1970). In one episode they met when they were kids, but in another they met when they were in the Army and in a third episode they met when they were both on the same jury!
- Possibly tripped over in Sledge Hammer!. depending on your interpretation of where the second season is placed. Since the first season ended with everyone dying in a nuclear fireball, the second season started with a disclaimer explaining that these episodes were set five years earlier. It's possible it was intended to convey that there was a five year gap between the second last and last episode of season one, therefore having a place for season two. Alternatively, if the second season is a prequel this creates a problem given the fact that the main characters met in the first episode, and weren't partners before.
- Community established in "Foosball and Nocturnal Vigilantism" that Jeffrey and Shirley met for the first time when they were 12 - but it wasn't until this episode that they realized it. While it was a very memorable experience, it was also very traumatic for both of them and resulted in major personality shifts for both of them. In effect they are very different people than when they briefly met as kids.
- The episode "Heroic Origins" crosses this trope with One Degree of Separation. Turns out Jeff briefly met Britta while he was still a lawyer, Troy threw some paper at Abed while they were both in the same frozen yogurt place, etc.
- Coupling did this in the episode "Remember This", which had flashbacks to a party several years ago that all the main characters attended before they'd all met one another and become friends. The point was to backdate the Unresolved Sexual Tension of Beta Couple Patrick and Sally, whose relationship had been simmering for two series already.
- Leverage did an episode of this in "The Rashomon Job." Though none of the characters meet directly.
- Farscape used this as a clue in the episode "A Human Reaction". The aliens could only create people from John's memories so after a while John realised that everyone around him was someone he had met, generally in some obscure way, before.
- Doctor Who: In the Tenth Doctor's final episode "The End of Time", he checks in on each of his companions before regenerating, ending with Rose Tyler. He visits her on New Year's Day 2005, the year she first meets him in his ninth(ish) incarnation. When she later (from her perspective) sees the Doctor turn into the random drunk she met in a London alley on New Year's, she makes no mention of it.
- In the second season of Telltale's Sam & Max: Freelance Police games, it's revealed that Sam built Bluster Blaster, an arcade game he met earlier in the series and showed no signs of recognising, when he was a preteen.note Sam and Max lampshade this:
Max: Funny, though. All this time we've spent talking to the COPS, and you never once mentioned you're the guy who built Bluster Blaster.
Sam: Just never seemed relevant, I guess.
- In Silent Hill: 0rigins, the prequel to Silent Hill, the only unique characters to the game are Travis, his family, and the Butcher.
- Averted in Professor Layton and the Last Specter. It's the fourth game in the series, but set first in the timeline. However, it still features appearances by Granny Riddleton, Inspector Chelmy and Barton, who chronologically first meet the Professor later. To avoid plotholes, the Professor and Luke never cross paths with them, only Emmy does (she never appeared in the earlier games). In fact, Granny Riddleton quickly goes on vacation and leaves her cat behind to perform her usual job, so the Professor never sees her. In Miracle Mask, Granny appears, and even meets the Professor, but she disguises herself and uses a pseudonym for no apparent reason, and in all other occasions when she appears she pretends not to know the heroes, so canon is preserved nonetheless.
- Metal Gear Solid managed to retroactively pull this. The prequel Metal Gear Solid 3: Snake Eater almost completely averted it, with Ocelot and Big Boss as the only characters from later in the timeline to show up. Metal Gear Solid 4: Guns of the Patriots, however, retconned it so everyone of importance from all the games (including 3) turned out to be deeply involved in the Gambit Pileup. SIGINT and Para-Medic were actually DARPA Chief Donald Anderson and Dr. Clarke, respectively, and both of them were founding members of the Patriots alongside Big Boss. note
- Though most of the characters in Metal Gear Solid 3 avert this, the game did manage to incorporate the titular nuclear-armed mecha into the story, even though it takes place about three decades before it was supposedly invented. The first game told us that Metal Gear was invented by Drago Pettrovich Madnar in the 1990s, but apparently the concept was actually developed—in full— by Aleksandr Leonovitch Granin in 1964.note We just never heard about Metal Gear for thirty years because the Soviet Union refused to fund Granin's design, so he sent the blueprints to a friend in the United States...who happened to be Otacon's father. Why Otacon never thought to mention this in the original Metal Gear Solid is anyone's guess.
- Characters who appeared in Namco × Capcom and Endless Frontier already know each other by Project X Zone.
- That's just the start. Characters know each other from other crossovers, such as Marvel Vs Capcom 3 or Street Fighter X Tekken. Several also recognize each other by reputation if they have a good reason to, such as people with knowledge of demons, like Arthur or Morrigan knowing of Sparda and figuring out Dante is his son.
- The original Tomb Raider features Lara Croft meeting Larson and Pierre Dupond for the first time. Tomb Raider Chronicles has the two appear as a pair of antagonists for a flashback level, and the dialogue makes it clear that both have crossed paths with Lara before.
- Parodied in PvP when the main characters were brought back in time by a magical d20 and stumbled across Skull. When they get back, they ask him why he never mentioned meeting them before. He says he "used to drink a lot back then".
- Notably averted by The Order of the Stick, despite being a continuity-heavy series that actually has fairly important prequels.
- The prequel Start of Darkness (the story is the trope namer for eponymous trope) almost exclusively follows Big Bad Xykon and his Dragon Redcloak, during which time they do not interact with any characters who weren't, at best, Posthumous Characters in the main comic. Mostly it shows characters who never appeared and will likely never appear in the online comic that influenced the lives of Xykon and Redcloak. The closest anyone gets to interacting with any members of the main or supporting cast is when Eugene Greenhilt (father of the comic's main character) walks in on Xykon dueling and killing his mentor, (which had been mentioned in the comic) and Redcloak's brother Right-Eye trying to help Eugene kill Xykon so that Right-Eye can escape being Trapped in Villainy.
- The other prequel, On the Origin of PCs, focusing on the heroes, doesn't have characters meeting before what was established in the main plotline as their first meetings: Roy and Durkon were friends before the Order formed, but the others only met them and each other right before the main events of the comic.
- Hercules: The Animated Series has Herc being quite the hero, even though much later, in the movie, he admits he's never done anything heroic to the disenchanted citizens of Thebes. He spent far more time causing accidents, and never went to Thebes in the series (usually in Athens, but went almost everywhere else in or near Greece besides Thebes). A more blatant continuity error is how Hades knows of and plots against teen Hercules in the series, even though in the movie he thought Hercules had been killed as a baby, which was excused by the writers to have him causing trouble. At the very least though, in the one episode Megara appeared, they hurriedly had both she and Hercules lose memory of each other so that they could meet again in the movie.
- Spoofed repeatedly on Futurama, which features Scruffy the Janitor, a fellow who meets the cast for the first time... every time he appears. Whenever Scruffy enters a scene, there's usually a mention of how he has no idea who any of the main characters are, and none of them know who he is, either, thus deliberately contradicting all his prior appearances. This leads to such lines as "Boy, I've never seen [Bender] so down, or ever before."
- Bonus points for Scruffy's first appearance being in the non-canonical Anthology Of Interest.
- The second movie plays with the spoof when it reveals that Fry has both Scruffy's home and cell phone numbers on his speed dial.
- And again in "The Tip of the Zoidberg" when the crew try to get Zoidberg fired. Farnsworth suggests firing Scruffy instead and is met with a loud chorus of protest.
Amy: OVER MY DEAD BODY!
- My Little Pony: Friendship Is Magic: Averted in "The Cutie Mark Chronicles". The main characters have not met, but all experience life changing inspiration by simultaneously witnessing Rainbow Dash's first Sonic Rainboom.
- A The Simpsons flashback episode showed that Homer and Marge had briefly met and shared their first kiss as children, but due to Marge's straight brown hair and
Homer'sElvis Jagger Abdul-Jabbar's patch over an injured eye, didn't recognize each other when they attended high school together.
- One flashback episode shows Homer meeting Ned Flanders while Marge was pregnant with Lisa. A later flashback episode shows Homer and Marge meeting Ned and Maude while both couples were childless.
- As with Futurama, spoofed in the early years with Mr. Burns. In his very first appearance, he tells Homer, "Ah, Simpson, at last we meet." Was true at the time, but a couple of later flashback episodes showed that he had already met Homer twice before at least. Of course, this was all part of a then-Running Gag that Burns could never remember who Homer was and had to be corrected.
Burns: Smithers, who is this man?
Smithers: Homer Simpson, sir; one of your drones from Sector 7G.
Burns: Simpson, eh?
- In the Steven Universe episode "Jail Break", Steven meets Ruby and Sapphire (the Gems that make up Garnet) for the first time. However, four seasons later, "Three Gems And A Baby" showed that Garnet unfused when Steven was an infant, but this left a bad impression on him.
- Subverted in Star Wars: The Clone Wars. Throughout the show's airing, a Star Wars fan worth their salt would probably be thinking "Hey, how is Anakin interacting and fighting with Count Dooku and Grievous when they only officially met in Revenge of the Sith, since Anakin was obviously referencing the battle on Geonosis when he says his powers have doubled? Or when Anakin joked about Grievous' height?" It's only upon looking back at the series that it's apparent Anakin never actually met General Grievous, making his quip valid. As well, the creators did try to cover their bases with Dooku by making their final clash in the series rather climactic and dramatic, justifying Anakin's claim of his powers having doubled since such a fight.
- BoJack Horseman: Bojack and Diane seem to meet for the first time in the first episode when she becomes his biographer and he realises that she's dating Mr Peanutbutter, but a later episode reveals they actually met earlier at one of Mr Peanutbutter's halloween parties when she approached him to gush over what a big Horsin' Around fan she was. He paid her no attention at the time, though, and completely forgot the event, and Diane presumably never reminded him either out of embarrassment at her fangirlness or because she was focused on charming him into opening up so she could write her book.
- A flashback in the Peanuts TV special Snoopy's Reunion not only retcons the backstory of how Charlie Brown obtained Snoopy seen in both the strip and Snoopy, Come Home, but shows that Sally and Linus were already a part of Charlie Brown's life at that point, with Linus accompanying him to the Daisy Hill Puppy Farm to pick out Snoopy. In the comic strip Snoopy was around long before Linus (then an infant) was introduced, and Sally wasn't even born yet.
- A Pup Named Scooby-Doo. It's presumably canon to What's New, Scooby-Doo? thanks to a Mythology Gag featuring an Art Shift to the former show's style in a flashback, but from there most incarnations that explore the gang's backstory have them meeting in their teens (until SCOOB!, that is).