Chuck Cunningham Syndrome / Western Animation

A

• Adventures of the Gummi Bears:
  • Cavin comes down with a nearly lethal case. Cavin is originally the main human character, meeting the Gummi Bears in "A New Beginning". The page (a knight-in-training) to head knight Sir Tuxford, it is though him the audience is introduced to the Gummi Bears. It is also through Cavin that Zummi gets his Gummi medallion, and is able to open the Great Book of Gummi after it has been sealed shut for centuries. After "A Gummi By Any Other Name", Cavin and Princess Cala share the role as the Gummis' human confidante. Still, without explanation, Cavin vanishes after "The Crimson Avenger" midway through the second season. Cavin's not seen nor heard from again, that is until near the end of the third season ("Knights of Gummadoon"). Cavin disappears again for several episodes, until finally making a full recovery in Season 4.
  • Unwin, Sir Tuxford's page and a bully to Cavin, isn't so lucky. He disappears after Season 4.
  • Unwin, Sir Tuxford's page and a bully to Cavin, disappears in the last couple seasons.
• All Grown Up!: Some of the characters from the original series, with one of the, being Pepper, one of Spike and Fifi's puppies, is not seen or mentioned. Only her brother, Spiffy is seen but he doesn't really show up again, afterawards.
• The Amazing World of Gumball:
  • Molly Collins appeared in background scenes in the first season, before disappearing halfway through the second. Eventually, it was revealed that she had been taken to a nightmarish void in reality because the world itself deemed her boring and erased her from existence, only to be rescued by Gumball and Darwin. Afterwards, she made several more appearances, subverting the trope.
  • Likewise, Rob suddenly stopped appearing in the second season because of the same reasons as Molly. However, he wasn't rescued like her, but escaped by himself, horrifically disfiguring himself in the process. He has since appeared frequently as a vengeful villain.
  • Rachel Wilson (Tobias' older sister) was a major character in the first season episode "The Party", then she only appeared in some background shots in the rest of the season. Since the second season, she no longer appears at all, even in scenes that feature her other family members. Reportedly, several of the show's staff (including the show's creator, Ben Boquelet) disliked her and her character design. She is, however, mentioned in the Season 5 episode "The Matchmaker", so we know that she wasn't sent to the void. In an episode of the show's spinoff Darwin's Yearbook, Tobias reveals that she hasn't been seen again because she's gone... to college.
  • Ocho was strangely completely absent in Season 3 aside from one background cameo in "The Safety", with no explanation for his absence, but returned in the following season and has since received a few episodes that focus on him.
  • Several background characters who appeared in multiple episodes have disappeared in Season 6, such as Mr. Poop and the chicken waiter.
• American Dad!:
  • Debbie Hyman first appeared in Season 2 as the first girlfriend Steve actually managed to have for more than one episode, although their relationship came to an abrupt end at the end of her 2nd appearance a few episodes later. Aside from an indirect reference, she was completely absent for the following season. She later returned for "Escape from Pearl Bailey" and "Bar Mitzvah Hustle" where she and Steve made up and became a couple again, only for them to once again break up but rekindle at the end of both episodes.^note Though the rekindling in the latter only happens in a deleted scene To date, her only other appearances since "Bar Mitzvah Hustle" have both been in the milestone 100th & 200th episodes, but only in brief non-speaking cameos, presumably for both episodes to be filled with as many recognizable characters as possible, as well as the episode "Railroaded" where she is among several other minor characters on the news as political insiders.
  • Despite her and Steve becoming a couple in "Spelling Bee My Baby", Akiko Yoshida (Toshi's sister) never appeared again and Steve went back to being single. To date, her latest appearance was a non-speaking cameo about four and a half years later in "The Talented Mr. Dingleberry" where she (along with her father, another victim of this trope) can be spotted in the audience during the talent show.
    • Akiko's mother Hiko also suffered a similar fate. Properly introduced in Season 4 (after a case of Early-Installment Weirdness in Season 1 where she was shown in a design drastically different from her current look), she would go on to appear at least once in every subsequent season (barring the 7th) usually with a speaking part. Following her very big role in "Spelling Bee My Baby" and a brief non-speaking cameo in "The Missing Kink", she disappeared from the show completely, only reappearing for another brief non-speaking cameo in "The Two Hundred" nearly three years later.
  • Greg & Terry's daughter Libby was a pretty big part of the plot for her debut appearance in "Surro-Gate" and she would eventually go on to appear at least once in every season afterwards. However, starting with the 11th season, when Mike Barker (series co-creator and voice of Terry) left the series due to creative differences, Libby's first acknowledgement afterwards was in "Roger's Baby" when Francine mentions her (though not by name) as part of the numerous times where she's been pregnant, and this being more than two years since her last appearance in "A Boy Named Michael". She finally returned for a non-speaking cameo in "Stan & Francine & Connie & Ted", more than four-and-a-half years since her last appearance.
  • Over the years, the show has had a habit of introducing characters (usually ones who are neighbors of the Smiths) who will start off as an Ascended Extra only to fall off the radar completely after about a season or two, being relegated to background cameos (if even). Notable examples of characters who've fallen victim to this over the years include Linda Memari, Chuck White, and the aforementioned Hiko Yoshida.
• In American Dragon: Jake Long, Rose was separated at birth from both her parents and her twin sister to be raised by the Huntsclan. After the Huntsclan is erased from existence (long story), we catch up with Rose. In the revised timeline, she lives a normal life with her parents...but there is no sign of her twin sister. Apparently, the sister's whereabouts would have been a plot point had the series been given another season.
• Several characters in The Animals of Farthing Wood weren't killed off, but simply disappeared in Season 3. This includes Fox and Vixen's son Friendly, Kestrel, and the surviving blue foxes aside from Ranger. Friendly made a brief appearance in the second episode of Season 3, then was absent for the rest of the series without explanation. Word has it that the show's producers didn't like him and requested that he be dropped from the show. Kestrel's disappearance is actually consistent with the original novels, in which the character simply stops appearing around the fifth book in the series, with no specific departure arc.
• Animaniacs:
  • Lampshaded in an episode, where Rita and Runt are advertised as "Missing" on a milk carton. The "Rita and Runt" segments having been dropped in the latter half of the series' run, after which the characters themselves put in the occasional cameo appearance, but gradually disappeared — though they continued to feature in the opening credits, and were eventually restored for the direct-to-video movie Wakko's Wish).
  • Out of universe, their absence was explained because they wanted to focus on other characters, and because Rita was voiced by Broadway actress Bernadette Peters rather than a main cast member.
  • Minerva Mink's disappearance was more justified. Her cartoons were too risque, even by Animaniacs standards — of the two that actually aired, one had a nerdy werewolf who turned into a hunk under the full moon. The other had Minerva using her sex appeal to dispatch a dachshund named Newt — and the executives were afraid she'd be used in a lot of sexually unsavory fan art and fanfiction online. This was, of course, doomed from the start, and this became Minerva Mink's fate anyway, thanks to those two episodes.
• Dr. Weird and Steve originally appeared at the beginning of episodes of Aqua Teen Hunger Force but were replaced by Spacecataz in Season 3 and disappeared entirely. They did return for the movie and one final appearance in Season 8.
• Arthur:
  • In a couple of episodes, George has a sister who is around his age. She last appeared in the Christmas special and so far has not appeared again.
  • There's D.W.'s pet toad "Toady" from season 1. When she reappeared in season 7, it was implied that she had simply been living in the yard. She's gone again until 7 seasons later, but this time her disappearance is justified in-universe because she is now married to another toad.
  • Mrs. Fink and Miss Sweetwater (the other 3rd grade teachers) and their respective students, were occasionally featured in the early seasons, mostly to act as a foil to Mr. Ratburn and his students. They have consistently shown up as background characters, though.
  • While not truly Chuck Cunningham syndrome, Jenna the cat was much more of a major character in the earlier seasons (even receiving her own episode at one point), only to fade away as the series went on. She almost never even appears as a background character now.
  • Dr. Fugue, Arthur's strict piano teacher, had four appearances each two or three seasons apart. He hasn't been seen since "Arthur Unravels" from season 14, as the show is now past season 23.
• Avengers Assemble:
  • Due to an embargo on properties whose movie rights were controlled by 20th Century Fox rather than Marvel Studios, Fantastic Four-related characters like Doctor Doom, The Thing and Impossible Man and X-Men-related characters like Mojo all ceased appearing after the first season. Doom's absence was especially notable, as he had been a frequent adversary of the Avengers during Season 1, showing up to menace the team in four separate episodes (and having Continuity Cameos in two others).
  • Spider-Man showed up in several episodes as well, even becoming a reserve member of the team during Season 2. He didn't appear or even warrant a mention in Season 3, which was particularly glaring since that season adapted Civil War and brought back many heroes from previous episodes. He was presumably absent since his own series was in its final season and a replacement was already in the works, meaning Disney XD likely didn't feel like promoting a soon-to-be obsolete version of the character.
  • Season 4 revolves around a new team of Avengers being formed after the original Avengers go missing. The new group largely consists of former reserve members, but for some unexplained reason, Red Hulk and Songbird (who joined as reservists at the end of Season 3) were not included. They aren't even mentioned when Black Panther and Vision are contacting the new recruits. Red Hulk eventually does show up again, but it's an alternate version of the character who comes from a Bad Future.
  • Season 5 takes this even further, with the new writers ditching around half the team. The Incredible Hulk, The Falcon, The Wasp, The Vision and Thunderstrike all drop off the face of the Earth, and most of them don't even get mentioned.

B

• In the TV series for Barnyard, titled Back at the Barnyard, Otis' love interest, Daisy, and her son Ben Jr. are completely absent from the show, Daisy's been replaced by a new female cow named Abby, who is more of a rough-and-tumble tomboy who readily stands up to a threat and is treated equally amongst the guys; the strange part is Daisy's best friend Bessie continues to appear on the show. There was also Miles the donkey from the movie that disappeared, other than being mentioned.
• Max Gibson, the third most prominent character in Batman Beyond, behind the two Batmen, is not present or mentioned in either Batman Beyond: Return of the Joker or the Fully Absorbed Finale "Epilogue" from Justice League. This may be because most of the production team weren't very fond of her as she was forced onto them in order to allow a positive female character on the show.
• In Walter Lantz's The Beary Family, the family originally consisted of Charlie (father), Bessie (mother), Junior (son), Suzy (daughter), and their pet goose, Goose. Early into the series, Goose disappeared, then eventually Suzy was dropped without explanation.
• Beavis And Butthead: In the 2022 revival, many of the show's important supporting characters like Principal McVicker, Coach Buzzcut, Stewart, Daria, Todd, and the Burger World are either no longer around or Demoted to Extra in Stewart's case. The only returning characters from the 90s show are David Van Driessen and Tom Anderson. However, it's otherwise justified in that Beavis and Butt-head time-traveled from 1998 to 2022 and that long 24 year time gap is lengthy enough that a lot could have changed, including those major supporting characters moving away in Daria's case, changing jobs, or even retiring (and/or possibly even dying) due to old age.
• Bimbo the Dog from the Betty Boop cartoons. In the early shorts he was meant to be Betty's boyfriend, but come 1934, and the Hays Office objected to an interspecies relationship, forcing Fleischer Studios to abruptly drop Bimbo. He would never be seen again in the series.
• In the 2006 revival of Biker Mice from Mars, there are some characters from the original series who are absent.
  • Sergeant Scabbard, who was introduced in the original series' three-part finale "Once Upon a Time on Mars", is the only Martian mouse allied with the Biker Mice to not appear or be acknowledged in any capacity in the revival series.
  • The Biker Mice's allies Four-By and "Asphalt" Jack McCyber, who both appeared in two episodes in the original series, are unaccounted for. Four-By's case is especially noticeable since the Pit Boss appears in one episode of the revival and the original series had Four-By dedicate his life to meting out justice against the Pit Boss.
  • While the original series' central villains Lawrence Limburger, Dr. Karbunkle, and Greasepit appear in reduced roles, Karbunkle's masochistic lackey Fred the Mutant makes no appearances in the revival other than a brief cameo as a hologram projection in "Once Upon a Time on Earth".
• In Blazing Dragons, Sir Galahot and Sir Hotbreath, two of the Knights of the Square Table, never appeared in Season 2, in which the main focus was on Flicker, Loungelot, Blaze, and Burnevere, but Allfire, Griddle, Flame, and Count Geoffrey and his minions all had some appearances.
• Along with retaining the characters from the original 1930s books, the 1990s Blinky Bill animated series based on the books introduced many new characters made for the cartoon. When the animated series was rebooted in 2015, Marcia the mouse was the only character made for the 90s series who returned for the new show, disregarding other fan-favourite characters such as Flap the platypus and the Dingo family. Naturally, this angered fans of the original series, who were already divided on the reboot to begin with.
• In The Blue Racer, the main character chased after a Japanese beetle, which was clearly designed as an offensive stereotype of Asian people. The character was ditched halfway through the series for obvious reasons.
• Bob's Burgers:
  • Officers Julia and Cliffany suddenly disappeared after season 1, but they did make a few non-speaking background appearances in some episodes.
  • Jimmy Pesto last appeared in Season 11. Then, the creators discovered that his voice actor Jay Johnston had an alleged role in the U.S. Capitol insurrection and fired him. Following a silent cameo in The Bob's Burgers Movie, he returned in Season 14 now voiced by Eric Bauza.
• Bradley from Bojack Horseman, one of Bojack's costars on Horsin' Around. A subplot of season 3 revolves around the sequel series to the show that he's trying to make, and with Bojack's encouragement, he drops everything and moves back to California. After Bojack has a nervous breakdown and backs out while they're filming the pilot, Bradley is never seen or mentioned again.
• One of the many reasons why the fourth season of The Boondocks wound up being unpopular among fans is because many of the beloved side characters — Thugnificent, Gangstalicious, A Pimp Named Slickback, Cindy MacPhaerson, Ed Wuncler III, and Gin Rummy — all vanished without any explanation. Ed Wuncler Sr. is a zig-zagged example: despite previously being the Big Bad of the entire series, he is inexplicably absent from most of the fourth season. He suddenly reappeared in a single episode, "Begun the Clone War Has," which aired very late in the season and long after Ed's son, Eddie Jr. had been established as the new main villain of the series, making Ed Sr.'s sudden reappearance and subsequent return to limbo all the more conspicuous.
• Sharon’s brother in Braceface appears to be phased out of existence in the final season.
• In Breadwinners, the Bread Maker has a bitter rivalry with the Lava Mole, who is completely absent in Season 2 with no explanation.

C

• Caillou:
  • The puppets, who disappear after Season 3.
  • Julie disappears after Season 3 without any explanation. Grandma and Grandpa take over her duties as a babysitter in Seasons 4 and 5 instead.
  • Mr. Hinkle started appearing less after season 3 before disappearing and being replaced by a new character called Mrs. Howard in season 5.
• Captain Planet and the Planeteers:
  • In the earlier seasons produced by DiC Entertainment, the Planeteers had a minor recurring ally named Commander Clash. He is nowhere to be seen in the seasons produced by Hanna-Barbera.
  • Looten Plunder's henchman Argos Bleak disappears in the show's final season, being replaced by a pair of dim-witted lumberjack thugs named Oakey and Dokey Pinehead.
• CatDog has Lola Caricola, an intelligent bird introduced in the third season who was notably one of the few characters to be on good terms with CatDog. She didn't appear in any episodes after "The Great Parent Mystery".
• In Chip 'n Dale: Rescue Rangers there was one episode where Dale falls in love with a bat named Foxglove, who loves him back. Chip is also happy because he gets Gadget all to himself. Foxglove was never seen again, though she seems to appear in more Fan Fiction than not.
  • Disney Afternoon shows regularly only had a small number of recurring characters while most other characters, even main characters are limited to one episode. These one-shot characters, however, sometimes gained a lot of popularity and fans of their own, sometimes more than some main characters. Chip 'n Dale: Rescue Rangers had some more popular one-shots including the squirrel Tammy, the lab rat Sparky, Gadget's Evil Doppelgänger Lahwhinie and Gadget's father Geegaw who is only ever seen in a picture. This popularity mostly rose long after the show was produced in a time when there was neither a vocal fandom nor an appropriate means of communicating the popularity of a character to the makers, so none of them ever returned. Both Foxglove and Geegaw eventually returned in the Boom! comics.
• Codename: Kids Next Door:
  • Numbuh 12 defects to the Teen Ninjas ahead of her 13th birthday in her debut episode, however she never appears with them in any later episodes.
  • Numbuh 206 is an odd example, since the reveal at the end of the episode is that "he" was actually Numbuh 362 in disguise; the complete lack of mention of him in later episodes makes it unclear whether there even was a Numbuh 206 whose escape presented an opportunity for 362 to go undercover (thus also leaving it unclear whether he successfully escaped or got captured later), or if it was just an alias 362 created for the operation. That said, a character with 206's design does briefly show up during Operation: Z.E.R.O..
• Eustace's mother from Courage the Cowardly Dog, after her introduction in Season 1's "Mother's Day", made semi-frequent returns as a villain across Season 2, but then never showed up again after her first and only Season 3 appearance in "Scuba Scuba Doo". Justified by the fact that her actress, Billie Lou Watt, died before that episode had actually aired.
• In The Critic webisodes, all the characters from the TV series have disappeared (save for Jay Sherman and a brief appearance by Vlada). The worst of all this is that Jay's girlfriend Alice Tompkins is replaced with a Replacement Scrappy named Jennifer.
• Several characters from the Curious George movie who played fairly big parts like Maggie, Mr. Bloomsberry, and Junior are nowhere to be seen in the TV series.
• Cyberchase: Widget, a younger bird stored inside Digit's chest and occasionally helps him when it is necessary, stopped appearing entirely after the season 5 episode "EcoHaven Ooze" and hasn't appeared since.

D

• Sixth Ranger Hsien-Ko from the Darkstalkers cartoon vanishes in the final episode.
• Darkwing Duck: Tank Muddlefoot, elder son of the Muddlefoots and bully towards his younger brother, vanishes after the Christmas Episode. Creator Tad Stones thought the character was redundant and so dropped him from the series.
• Davey and Goliath: Davey’s friends (except Jimmy) are nowhere to be seen and are replaced with Jonathan and Nicky.
• Dexter's Laboratory:
  • After the episode "Trick or Treehouse", Mee Mee and Lee Lee were no longer seen or mentioned.
  • Mandark's sister Lalavava was never seen or mentioned after her first appearance except in the storybook "I Dream of Dexter". The last two seasons introduce Mandark's Hippie Parents and show his home life periodically, but seem to depict Mandark as an only child.
  • Action Hank and the Pony Puffs (Dexter and Dee Dee's heroes, respectively) also seem to have taken their leave after Season 2.
• Dora the Explorer:
  • Diego had an older sister named Daisy. She was replaced with Alicia once he got his show, even though the episode she was in revolved around her birthday. In Go, Diego, Go!, she's said to be in college and she was mysteriously aged up.
  • The series introduced the Explorer Stars in Season 3, only for them to disappear two seasons later.
• The second episode of Nickelodeon's Doug, "Doug Can't Dance", had Roger leading a different group of thugs than usual. These thugs appeared only in that episode. Justified in that "Doug Can't Dance" was the series pilot.
• DuckTales (1987) notably had quite a few recurring characters disappear without any explanation during its second season, including Doofus, three of the Beagle Boys (Bankjob, Babyface, and Bugle), and Admiral Grimmitz.
  • Bubba the caveduck also disappeared in the fourth season.
• In Doc McStuffins, Donny's friend Will disappears after season 1 while Doc's friend Henry disappears after season 3.

E

• Ewoks: There's Paploo, a prominent character in the first season. In the second season, he was reduced to a non-speaking cameo and the leading four do not even seem to notice his absence from their adventures.

F

• The Fairly OddParents!:
  • Remy Buxaplenty, rich bastard and Juandissimo's godchild is an odd example of this in that he is written out of the show at the end of his first appearance. Three seasons later, apparently due to viewer demand (and because he was one of Butch Hartman's personal favorite characters), he returns as a recurring antagonist to Timmy for three more episodes. After the third episode, though, he's not mentioned again, not even in Juandissimo's subsequent appearances. He actually appeared in a much later episode called "Country Clubbed", except with a redesign and a minimal role.
  • Back when Mark Chang was Timmy's enemy he had two friends on Yugopotamia named Jeff and Eric. They haven't appeared recently, not even in an episode that had Mark going back to his planet temporarily.
  • This might be the fate of Trixie Tang and her "friend" Veronica as of Season 9. Trixie has occasionally appeared in the background but she doesn't speak as her voice actress left and she hasn't been replaced. Similar fates had Timmy's former best friends A.J. and Chester, who in later seasons had occasional appearences with even less voice lines. Trixie's gimmick as a love interest that Timmy must win over using means other than magic was given to a new character Missy in Season 9.
  • Although not a straight-up example, after the first live-action movie, Tootie stopped appearing in the series proper and became relegated to the live-action movies only, which are still ambiguously canon. Her final speaking appearance was in "Lights Out" from season 7.
  • The Team Pet Sparky was introduced in Season 9 but doesn't appear in Season 10, even in a non-speaking cameo. There's no in-series reason for his exclusion. He was removed due to poor reception (it didn't help that most of the crew hated him just as much as the fandom did).
  • Cosmo and Wanda's son, Poof, only appears in one episode in the final season ("Certifiable Super Sitter"). This was done to "prevent too many characters from being in one episode", with all the plot difficulties that come with it. Making it stranger is that his Evil Counterpart, Foop, did make frequent appearances throughout the season. Poof was also absent in the live-action Sequel Series, The Fairly OddParents: Fairly Odder.
  • Francis, the school bully, simply stopped appearing after a final cameo appearance in the Season 7 episode "Dad Overboard", with nobody ever even mentioning his existence again.
  • Recurring antagonists the Pixies stopped appearing after the season 6 episode "The Fairly Oddlympics".
  • Cosmo's mother, Mama Cosma, had semi-frequent appearances before disappearing entirely after season 6.
  • Anti-Cosmo and Anti-Wanda stopped appearing after "Balance of Flour", only getting indirect mentions as Foop's parents.
• Even outside of the many incidental cutaway characters, Family Guy has a few.
  • The trope is directly lampshaded in the episode "The Father, the Son and the Holy Fonz", in which Peter starts a religion based on Happy Days.
    Peter (preaching): Let us contemplate the mystery of Richie's older brother Chuck, who ascended the stairs with his basketball in season one, and never came down again.
  • Brian's gay cousin Jasper, who used to appear a couple of times per season, disappeared after the gay marriage episode. He wasn't very popular, so that may have had something to do with it.
    • Jasper appeared in the episode "Brian's Play" talking with Brian on Skype and the episode "Life of Brian" at Brian's funeral.
  • Joe Swanson's own children seem to disappear without a trace. Kevin Swanson appeared in the first 3 seasons, then just disappeared for years, though he had a few non-speaking cameos. Years later after his last speaking role, Peter questioned his disappearance out of curiosity. Joe explained Kevin died as a soldier in Iraq with hardly any emotion. Seth MacFarlane felt Kevin was not a very interesting character to write for. Kevin is brought back in "Thanksgiving", where it's revealed he faked his own death and deserted after witnessing the horrors of war in Iraq.
    • But then Kevin disappears again from "Turkey Guys" until "Cop and a Half-Wit". He is even absent from the hospital scene after Joe's accident in "Brokeback Swanson".
  • Parodied in "Spies Reminiscent of Us" when Chris enters in an exchange program and switches places with an elephant (don't ask). At the end of the episode, Brian stated that it was a joke for the episode.
  • In Carol Pewtershmidt's first appearance she had just given birth to a baby boy, but in her subsequent appearances, he is nowhere to be seen. Though he could be living with his biological father.
  • Chris was set up to be with a girl named Anna in "Long John Peter" but, after that episode, she's never mentioned again and Chris is seen trying to get with other girls after that. That also happened with Herbert's niece in the Valentine's Day episode.
  • Cleveland Jr. only appeared once post-3rd season. Although he did return following the cancellation of The Cleveland Show.
  • Death disappeared for a long while, though he reappeared in "Friends of Peter G." to show Peter what life would be like if he continued to binge drink.
  • Peter's biological father was shown only once and was brought up in a few mentions. Justified, considering the fact that he lives on the other side of the Atlantic.
  • Meg has a group of friends; Ruth, Esther, and Patty. In earlier episodes, however, a blonde girl named Beth was with them, but as of Season 6, she never appeared again — and was never able to develop further as a character as her other three friends have been developing lately.
  • Dave and Dottie Campbell, a nudist couple, made a couple of appearances in season three, cameoed in the DVD version of "Stewie Griffin: The Untold Story," then they pretty much vanished.
  • Brian's therapist, Dr. Kaplan. He made a handful of appearances across seasons 2 and 3, then disappeared entirely.
  • Quagmire's long-lost daughter Courtney meets Quagmire in Season 17's "No Giggity, No Doubt" and moves in with him but is never seen or mentioned again after that.
  • Joyce Kinney, who was Diane Simmons's replacement and set up to be a rival of Lois has barely appeared outside of the season she was introduced in despite the fact she's supposed to be the co-anchor alongside Tom Tucker, and has been largely forgotten about.
• Likely due to the extensive Retool that occurred between the first and second seasons of Fantastic Four: The Animated Series, many of the villains from Season 1 did not return for Season 2. In fact, just about the only bad guys to carry over were Doctor Doom, Galactus, Terrax (who ended up being retconned into appearing later than he actually did) and the Super-Skrull. Lavinia Forbes, the team's annoying landlady, also disappeared after the first season (as did her dog). In the case of Namor and Puppet Master, they were due to return but the third season never materialised.
• When Fireman Sam Shifted to CGI in 2008, Bella Lasagne and her cat Rosa disappeared from the series, with Bronwyn Jones and her cat Lion filling in their space. While Bella eventually returned as a Drop-In Character in Series 10, Rosa has never appeared again.
• Due to the changing nature of the franchise The Flintstones offers some changes:
  • Upon the aging up for The Pebbles and Bamm-Bamm Show, Dino, Hoppy and the Great Gazoo were gone, new pets in their place. It then went the other way during the show's later episodes: the new pets are gone but Dino is back.
  • In The New Fred and Barney Show, all the pets are back. Gazoo was still gone.
• Franklin is rather bad for this, but perhaps the worst example is the character of Moose. An entire story in the first season of the program, based on the books, was dedicated to introducing this character and his acceptance within the close-knit community. In the episode, he finally joined Franklin's class and became his good buddy, but he was never again seen on the series and no explanation whatsoever was provided for his absence.
• Lampshaded in the second season of Freakazoid! Lord Bravery, Fanboy, and the Huntsman are upset about their sequences being trimmed down to nothing in the second season and want something to do. Freakazoid makes them wash his car and that's the last we ever see of them.
  • Ironically, Freakazoid's alter ego Dexter Douglas is only seen twice in the second season and never shows up again.

G

• The first two episodes of the Garbage Pail Kids Cartoon established Trash Can Ken as the leader of the Garbage Pail Kids, but he is nowhere to be seen in the remaining eleven episodes.
• The DiC Entertainment continuation of G.I. Joe: A Real American Hero quietly wrote out the Crimson Twins (Tomax and Xamot), with no word what happened to them after the movie and the closest they get to an appearance being their company Extensive Enterprises being featured in the two-part episode "Long Live Rock and Roll". Zartan also remains unaccounted for, as are many of the characters introduced in the aforementioned movie.
• Grizzly Tales for Gruesome Kids dropped Uncle Grizzly's pet spider Spindleshanks after the fifth series truncated the stop-motion Framing Device so that all we saw of Uncle Grizzly after he welcomed the audience and started telling the story was the episode occasionally ending with stock footage of Uncle Grizzly laughing maniacally after the story reached its conclusion. By the seventh and eighth series, Uncle Grizzly himself stopped appearing and was replaced by the Night-Night Porter as the eponymous grizzly tales' narrator to accommodate the retool changing the setting from the Squeam Screen theatre to the HotHell Darkness.

H

• Robin in the first two seasons of Harley Quinn (2019). After Gotham descends into anarchy in the start of the second season, Damian explains to Gordon (while wearing one of Batman's suits that clearly does not fit him) that he intends to take up the mantle in his absence. However this is never mentioned again and his absence is particularly notable in the Batman-centric episode that not only spends a great deal of time at Wayne Manor, but also focuses on how Gotham's heroes have been getting by without the Bat.
• Hey Arnold!:
  • Anybody remember Ruth P. McDougal (the sixth-grade girl Arnold had a crush on)? She wasn't seen much after the Valentine's Day episode where Arnold tries to go on two dates at once and finds that Ruth isn't the dream girl he thought she was, as she was very boring, very shallow, and not very bright.
  • Mr. Smith, the mysterious character who lives in the boarding house and even had an episode revolved around him, was never heard from again after the first season.
  • The first episode with Coach Wittenberg mostly revolved around his son, Tucker, and Arnold helping him get his father's approval. Tucker vanished after that, even though Coach Wittenberg continued to appear, along with the introduction of his (ex-)wife Trish (presumably Tucker's mother?) Tucker didn't even show up when the two remarried. He does finally reappear in The Jungle Movie, where he made a silent cameo along with his parents.
  • Lana, a woman who lived at the boarding house during the early episodes. The writers originally planned for her to have a crush on Arnold, but since she was a woman in her mid-20s at the youngest, this didn't go over too well with Nickelodeon, so her character disappeared after the first season. However, this could have been Hand Waved by saying she moved out... Until for whatever reason, she shows up in the finale, apparently still living there this whole time.
  • Harvey the mailman is pretty much one. He appeared regularly from 1996 to 1999, but by the Turn of the Millennium, he hardly ever appeared on the show, making only background appearances here and there. For unknown reasons, Harvey's voice actor Lou Rawls stopped doing voice work for the show after the Season 4 episode "Chocolate Turtles." Like Tucker, he showed up The Jungle Movie in a cameo.
  • Ludwig, a bully who competed with Wolfgang in his single episode never appeared again, despite him becoming friends with Wolfgang at the end of the episode.
  • Torvald disappears after only three episodes (the last of which is only a brief silent cameo).

I

• I Am Weasel's sexy nurse, Loulabelle, made her debut in the season 2 premiere, but was not seen or mentioned since the season 3 premiere. It was already implied in one episode that she didn't like Weasel, so that's one reason. The more likely reason was Cartoon Network didn't approve of the dumb blonde stereotype she perpetuated, or because she was too similar to Hello Nurse.
• The first season of Iron Man: The Animated Series gave the Mandarin his own Legion of Doom, who effectively served as Evil Counterparts to Iron Man's Force Works team. Season 2 downgraded most of the Mandarin's lackeys to guest star status, but a few of them, namely Dreadknight, Canon Foreigner Hypnotia and Living Laser, completely dropped off the face of the Earth and never appeared after the first season.
  • The above was for the most part the fate of the majority of Force Works team, as they all felt betrayed by Tony Stark's duplicity in faking his death. Longtime friend James "Rhodey" Rhodes and would-be Love Interest Julia "Spider-Woman" Carpenter would stay on and remain regular presences in the series, but Hawkeye, The Scarlet Witch and Century would pretty much fall off the face of the Earth, except for Clint Barton making a couple of cameos as a semi-antagonist.

J

• In the first episode of the 1980's The Jetsons revival, Elroy got a pet alien named Orbitty who hatched from an egg and was the last of his species. He made regular appearances throughout the series until the season 2 finale "A Jetsons Christmas Carol", after that he was dropped from the series (aside from a non-speaking cameo) and was never seen again (except in an episode of Harvey Birdman, Attorney at Law), not even in the movie.
• Johnny Bravo:
  • The first season had Jungle Boy, a character who appeared in several episodes (and may have been intended to star in a backup feature like The Justice Friends or I Am Weasel), but who vanished come the second season and the retool the show underwent after Kirk Tingblad replaced Van Partible as showrunner. Not even the fourth season, which brought Van Partible back, had him featured at all.
  • Bobo, the head chef at Pops' diner, was a minor recurring character in the second season before only appearing in one episode of the third season and disappearing altogether by the fourth season. Fellow season two additions Pops and Carl fared slightly better, with the former only having a cameo in one episode and the latter being reduced to a minor recurring character with only one spotlight episode.
  • Two other recurring characters from the Kirk Tingblad era who noticeably disappeared from the show once Van Partible returned were the Prospector and Master Hamma.
  • The 2011 animated film that only aired overseas titled Johnny Bravo Goes to Bollywood eschews Carl Chryniszzswics, Pops and Little Suzy, with Johnny's mother Bunny being the only character from the series besides Johnny himself to return.
• In Jumanji: The Animated Series, the villainous "Stalker" character was introduced in the sixth episode, who looked somewhat like the Grim Reaper. The other villains feared and worked for him, which seemed to be setting him up as the main villain of the series. Unfortunately, he only appeared in two episodes and never reappeared, despite the ending of both episodes hinting at a reappearance.
• In the second season of Jungle Junction, Carla the koala vanished completely.

K

• KaBlam! had a number of these. Sniz and Fondue's room mates, Bill the Lab Guy's daughter Quirky from Action League and Grubby Groo from The Off-Beats (The only adult in that entire short!).
  • Eventually mid-season 3, Sniz and Fondue themselves were Chucked- the creator of the shorts left Nickelodeon due to studio politics. The Off-Beats themselves also got the treatment after the second season.
  • Life With Loopy had Stacey, who had first appeared in "Larry's Girl" at the end of the third season as Larry's girlfriend, setting her up for more appearances. By the time season four came around, she was nowhere to be seen and was never mentioned once (though Larry going Out of Focus that season might have had something to do with it). Larry's favorite TV stars, Charlie Chicken and Turkey Thompson, also disappear in the fourth season after being semi-regulars in the first three seasons.
• Star quarterback Brick Flagg from Kim Possible showed up here and there, but he sort of vanished after a while. Although his no longer appearing was eventually justified at least for the last season, he graduated by then. He wasn't exactly the brightest bulb when off the football field, and it was mentioned that he'd finally graduated after being held back a few years. (He even votes for one of his opponents during the school election. Not that it mattered much.)
  • Zita, Ron's love interest, disappeared after her second appearance without any mention of her by the main characters. She returns in the Grand Finale as Felix's girlfriend.
• Several recurring characters in King of the Hill just disappeared over time like Eustace and his geeky son Randy, who were rivals to Hank, Bobby and their friends in the earlier episodes but they vanished over time too. Bill's iguana Lenore only makes a one-episode appearance, and his girlfriend Laoma, who was Kahn's mother. A season finale episode ends with her living with Kahn and her and Bill in a relationship, but come the new season she's inexplicably gone. The writers apparently wanted to keep Bill alone and miserable.
  • In the episode in which Bobby breaks up with Connie, he meets a new girl named Debbie at the mall. They get along fine and are set up to be a couple; come next season she is never seen nor mentioned again and Bobby is back to being single. This happened quite a few times, actually: Bobby would meet a new girl who clearly liked him and they are seen together at the end of an episode. Invariably the girl is never seen or mentioned again because Bobby must always lose when it comes to romance.
  • There's also the blonde kid Garth, who appears in the Straight Arrow episode and is implied to be Boomhauer's illegitimate son.
  • In the second episode, "Square Peg", Peggy is seen talking to several other women on a bench at a Little League game. Come the next episode, they have vanished and Peggy's only friend is Nancy. This may have been a retcon for later episodes that had Peggy worried that she didn't have enough female friends.
  • Those women do appear in the episode in which Khan and his family move in three episodes later but as mentioned previously they don't appear again after that.
    • Those women appear again rather infrequently and at times not all together. One episode in season 2, "Peggy's Turtle Song", features them delivering a very bizarre Laughing Mad moment.

L

• In the Lloyd in Space episode 'Nora's Big Date', Lloyd's mom falls in love with a ship mechanic named Herb. Following a bunch of miscommunication from Lloyd, it ends on a sweet note where Lloyd realizes his mom truly loves Herb and that he's been feeling moreso jealous rather than actually suspicious. However, after this episode, Herb never shows up again in the show and is never mentioned again. While his debut episode might have been his only episode, it's strange how Nora forgot about him immediately after. He could have made an excellent father figure for Lloyd, with his actual dad not being around and all.
• Almost all of the original 1930s Looney Tunes stars such as Bosko, Buddy, and Porky Pig's friends have been missing from the series for decades.
  • Bosko's case was that Rudolf Ising, his creator, took the rights of the character with him when he moved to MGM, where he used him in Happy Harmonies as a recurrent character. Nowdays is extremely rare for Bosko to be shown on any Looney Tunes production due Unfortunate Implications about him originally being an African American caricature of the time, and when is show, he is always explicitly identified as an "inkblot" Cartoon Creature (with his last official appearence to the date being in a panel from DC Looney Tunes #235 in 2017). It doesn't help that his esoteric nature compared to the mainstream Looney Tunes (due to his cartoons being off the air since the 1980s) and vague personality do not make him a popular character among fans. Other characters from the era (especially those preceding the Hays Code) dissapeared due being considered too risque or violent for today's audiences.
  • Foxy was a character that appeared in three Merrie Melodies shorts in 1931 before completely vanishing. He was originally intended to be that series' central character, but his disappearance is justified, because he was a Captain Ersatz of Mickey Mouse (he even provides that trope's page image), to the point that Disney threatened to sue Warner Bros. after his third cartoon (he was meant to make a fourth appearance in "You Don't Know What You're Doin'!", but was replaced by Piggy, who himself disappeared after two shorts). When they came back for Tiny Toon Adventures, like Bosko and Honey, they were also redesigned.
  • After Harman and Ising ended their association with Warner Bros. in 1933, Buddy, an obvious Expy of Bosko, was created to be the new focal character of the Looney Tunes shorts. However, Buddy's cartoons were so poorly received that his character was eventually retired in 1935 to make way for Porky Pig and his friends as the shorts' new stars. Though much like Bosko and Foxy, Buddy would eventually return in Animaniacs, where he was reimagined as a Butt-Monkey who is always falling victim to the Warners' zany antics.
  • The 1935 Merrie Melodies short I Haven't Got a Hat was the debut of several characters meant to become a new recurring cast, made up of Porky Pig, Beans the Cat, Kitty, Ham and Ex, and Oliver Owl. These characters subsequently became the new main characters of Looney Tunes, with Beans the Cat intended to be the shorts' headlining star. However, Beans, much like his predecessor Buddy, was also met with poor reception, and by 1937 all of the characters introduced in I Haven't Got a Hat except Porky had disappeared, though Beans would appear as a picture cameo in Space Jam and Ham and Ex would also make a cameo appearance in Looney Tunes: Back in Action nearly 70 years later.
  • In 1937, a character named Gabby Goat was introduced, intended to be a hot-tempered Foil to Porky. However, audiences found him too obnoxious to be funny, and he only lasted three shorts before being removed. Early storyboards indicated that he was going to make a fourth appearance in the 1938 cartoon Porky's Party, but was instead replaced by an unnamed penguin character. One of his cartoons, Porky's Badtime Story, was remade in color, with Daffy serving as his replacement. He would finally reappear 80 years later in New Looney Tunes.
  • Egghead had disappeared by 1940, with elements of his design and character absorbed into Elmer Fudd.
  • In a similar vein to Egghead, Happy Rabbit would also disappear by the end of 1940, as Bugs Bunny came to be fully realised. His final appearance was in Patient Porky (released about a month after A Wild Hare), at which point the only things differentiating him from Bugs were his zanier voice and personality.
  • In Chuck Jones' early years, he had a character called Sniffles the Mouse, who appeared quite frequently between 1939 and 1941. By the time Jones grew the beard, Sniffles began to appear less and less (on top of being retooled into a Motor Mouthed trickster in the same vein as Friz Freleng's Little Blabbermouse, who also suffered this trope) until he vanished completely in 1946, last appearing in Hush My Mouse.
  • Strangely enough, Melissa Duck has been seldomly used in the Looney Tunes franchise despite being Daffy Duck's significant other for several years. Looney Tunes: World of Mayhem finally subverted this situation.
  • In the Seven Arts-era during the late '60s, some new characters were introduced, such as Cool Cat, Merlin the Magic Mouse and Bunny & Claude. While Cool Cat and his rival Colonel Rimfire sometimes appear in modern Looney Tunes works^note specifically The Sylvester and Tweety Mysteries, Tweety's High Flying Adventure, and Looney Tunes Cartoons and Merlin eventually came back in Tiny Toons Looniversity as Buster's mentor, Merlin's partner Second Banana and Bunny & Claude haven't really been seen since the Seven Arts-era. Justified, considering that the Seven Arts-era (and to a somewhat lesser extent, the DePatie-Freleng era) are widely considered the Audience-Alienating Era of the series.
    • Within the original series, several characters from the studio's heyday had disappeared after 1964, such as Foghorn Leghorn, Yosemite Sam, and (most shockingly) Bugs Bunny. However, a Mexican Captain Ersatz of Yosemite Sam was the antagonist of the DePatie-Freleng era cartoon "Pancho's Hideaway".
    • The Seven Arts era upped the ante by removing every classic character except Daffy, Speedy, and Sam Cat. Even then, the latter only had one appearance in “Merlin the Magic Mouse” before also disappearing, while Daffy and Speedy appeared in no cartoons after See Ya Later Gladiator, with newly-created characters taking up the entirety of Warner Bros. output from then on.
  • Elmer Fudd appeared sparingly after 1959 and he eventually disappeared entirely after 1962's Crows' Feat (although Bugs mentions him by name in Mad as a Mars Hare, over a year after he stopped making appearances). This was because of the death of his voice actor, Arthur Q. Bryan. He was replaced by Hal Smith for the shorts Dog Gone People and What's My Lion, but the difference was obvious and he was completely silent in Crows' Feat before vanishing from the series. Mel Blanc voiced him a couple of times in commercials, but by his own admission he never quite got the voice nailed down. He eventually came back to the franchise after Mel Blanc died, which necessitated the replacement of nearly the entire cast anyway.
  • Tiny Toon Adventures brought Bosko, Honey^note who were redesigned into more of what Yakko, Wakko, and Dot would eventually be to avoid Unfortunate Implications, Foxy, Foxy's girlfriend^note christened "Roxy" and Goopy Geer back for cameos, in which they were hailed as talented veteran cartoon stars. Later, an episode of Animaniacs had Buddy make an appearance, but it was a lot less complimentary toward the character in question (turns out Yakko, Wakko and Dot were created just to spice up his notoriously boring cartoons, but they were ''too'' looney, and in the same episode, Buddy, who has the same voice as SatAm Robotnik, is revealed to be out for revenge on the Warners). Another Animaniacs episode parodying Betty Boop had Bosko briefly appear in the background. Unlike in Tiny Toons, Bosko kept his original design.

M

• My Little Pony 'n Friends had an ever-changing cast, as they tried to market as many ponies as possible. There were some characters that never faded like Wind Whistler or Fizzy but others disappeared without a trace:
  • Notoriously none of the ponies from the first special ever pop up again. You'd think they'd have a close bond to Megan or would at least pop up more, considering they saved the entire kingdom. Whenever the ponies go snatch Megan, she never says "Where's Firefly? Or anybody who was here last time?" It's especially unusual for Firefly to never appear as she was more-or-less G1's mascot.
  • It's most notable with the "baby" versions of several ponies. It's not 'til the TV series gets underway that they're treated like the toyline treats them (as daughters of the adult ponies they're named and designed for, existing alongside them.) This introduces a serious hole to the second special: it has has baby versions of two characters from the first special and two who will appear in future installments. If those are their daughters, then how come they're never, ever seen alongside their mothers? (Of course, maybe the ones whose adult versions were yet to appear are the same characters grown up; at least, that's how the fandom treats it.)
  • And around the final two weeks of the show's run, Megan outright stops appearing. This is a particularly notable example because Megan was the show's primary character up to that point, and had been one of the only two (alongside the dragon Spike) to consistently appear since the original TV special.
• My Little Pony (G3) continues the tradition from its predecessor, most notably with Kimono, who was said to be the wisest of the ponies and who's birthday is main focus of the first special, and Razzaroo, the protagonist and narrator of said first special. Neither is seen in any other episodes, beyond a few background cameos. Following the Soft Reboot into generation 3.5, where the entire cast was condensed into the Core 7, any character not a part of the group suffered this fate.
• My Little Pony: Friendship Is Magic:
  • Twist is a filly introduced as Apple Bloom's best friend in "Call of the Cutie". The two have a bit of fallout when Twist gains her cutie mark while Apple Bloom doesn't (Twist even says "We can still be friends, right?"), but this is not presented as anything particularly serious. In the same episode, Apple Bloom meets and befriends Sweetie Belle and Scootaloo, and forms the Cutie Mark Crusaders with them. For the rest of the show, the CMC become inseparable friends and are almost never seen apart, their bond and closeness becoming a major part of their characterizations. Twist, however, has since only appeared in the background, only receiving one more speaking role (in a season 2 episode "The Cutie Pox") since her voice actress moved sometime after the episode.
  • This is a fairly common fate for several of the characters' pets, which were introduced in the first couple seasons, featured in a number of episodes and in many cases largely faded from the spotlight afterwards. The most notable examples are Applejack's dog Winona, who ceases to see any use worth the term after the third season, and Twilight's owl Owlowiscious, who remains in use for about a season longer before fading from view. The most extreme example is Princess Celestia's pet phoenix Philomena, who appeared once in Season 1, was established as a rare and magical creature with a fleshed-out personality, and has never been seen or mentioned since. The only pet to stick around to the end were Fluttershy's bunny, Angel, largely because he's the only one who had consistent characterization, and Pinkie Pie's alligator Gummy.
  • Babs Seed is a cousin of Apple Bloom's, who showed up in season 3 for two episodes, together with some in-depth exploration of her character and the implication that she was going to be a Sixth Ranger to the Cutie Mark Crusaders. However, she never showed up again after her second appearance, and the biggest mention of her afterwards was in season 5 where we learn she got her cutie mark offscreen. Apparently, her voice actress had left the show and they didn't want to replace her out of respect, so instead just didn't have her character reappear. The comics do utilize her a bit more, though.
  • Coco "Miss" Pommel also fell victim to this trope once the Chanel estate sued Hasbro for likeness infringement. The most we hear of her after season 6's "The Saddle Row Review" is as an off-hand mention in season 7's "Honest Apple" (to provide an ugly outfit for Applejack to mock), and her sole on-screen appearances after said episode are blink-and-you'll-miss-it cameos in The Movie and Grand Finale. Evidently, the writers figured it was easier to just not use her anymore rather than refer to her exclusively as "Miss Pommel" in future episodes. She does get at least a bit more to do in the comic.
  • It can be easy to forget that the Cake family had a patriarch. Carrot Cake last had a speaking role in Season 5 while his wife and twin foals have had major roles in at least one episode of the four subsequent seasons. He still made appearances in the comic, but he was usually just there.
  • Rarity's parents largely faded from the show after Season 4, only making a background appearance in "A Hearth's Warming Tail" in Season 6 after having been absent throughout the intervening season, and a final cameo in the School For Gifted Unicorns in "The Ending of the End — Part 2". Their primary role in the show — to serve as Sweetie Belle's caretakers — is after that entirely taken over by Rarity, as Sweetie Belle is in most appearances shown living in Rarity's house rather than their parents', thus negating their only real narrative role.
  • Prince Blueblood, supposedly one of the highest-ranking royals in Equestria and Celestia's nephew, completely vanishes from the show after season one. Even though the royal ponies play a much larger role in later seasons once Twilight becomes a Princess, the show never acknowledges Blueblood's existence after the season 1 finale aside from very small handfull of blink-and-you'll-miss-it background cameos — he doesn't even take part in the Series Finale Big Damn Heroes moment that even movie-exclusive characters like Tempest Shadow showed up for.

N

• Thirty-One from Numberblocks only appeared in his figured-out form in "Figure It Out" and isn't seen nor mentioned again after this episode.

O

• Ozzy & Drix: The titular protagonists are the only internal characters from the original film to return, as Tom Colonic, Mayor Phlegmming, Leah Estrogen, The Chief, Mrs. Boyd, Bob and Shane were left out without any mention (justified in Mayor Phlegmming's case, since he was farted out of Frank in the final scene of the film).

P

• PAW Patrol: Shortly after she was born, Wally's unnamed daughter disappeared from the season. She hasn't been seen since Season 3; the series is currently on Season 9.
• On the British animated sketch show Planet Sketch there was a character named June Spume whose gimmick was that she could transform her body parts into musical instruments and play them. She didn't return for the second season, possibly because the writers ran out of ideas for her.
• Polly Pocket: Main antagonists Griselle Grande and granddaughter Gwen suddenly disppeared after Season 1. It wasn't until the last episode of Season 5 that they finally came back.
• Popeye had four nephews introduced around 1940 — as the series went on it was knocked down to three, then two. This was probably due to animation cost restraints, but it comes off as pretty creepy.
  • Hanna-Barbera's take on Popeye in 1978 brings back three of the nephews. But in 1987's ''Popeye & Son," the nephews and even Swee' Pea are egregiously left out in favor of Popeye and Olive having a son.
  • The Popeye's Cartoon Club webcomics by Something*Positive's Randy Milholland brought back the nephews...kinda.
• Postman Pat: A few key supporting characters; Miss Hubbard, Peter Fogg, Granny Dryden, Major Forbes, George Lancaster and Sam Waldron vanished when the series was revived. In the case of Granny Dryden, it can be inferred that she passed away.
  • When the series was retooled as Special Delivery Service, Mr. Pringle and the Pottage family also disappeared, with the former's role as the school teacher being taken by Lauren Taylor.
• In Puppy in My Pocket: Adventures in Pocketville, there was a supporting antagonist named Krakia, who was part of Eva's gang and was sent to the Big City to spy on Kate and Magic as they try to free Ava from the Pet Buster's prison-like pet mill. After the episode "The Last Piece", she does not make another appearance in the show, with her whereabouts unknown.
• Purno de Purno had several characters go through this:
  • Every single character with the exception of Purno disappeared after the first series.
  • Buuf, Prune's Love Interest, disappeared after the second series.
  • Dr. Ha Chiu, an Asian guy who runs an Asian store selling various potion-like substances, disappeared after the third series.

R

• The humans and Sophia Tutu on The Raccoons.
• In Ready Jet Go!, Face 9000's brother, Face 9001 only appeared in the episode "A Kid's Guide to Mars" and never came back again.
• Louis Tully in The Real Ghostbusters had a somewhat important role in seasons four and five, whilst the Sequel Series Extreme Ghostbusters that continued the events of the first show and referred it constantly, never even mentions Tully, as described in the Ghostbusters wiki: "making him the only person who was part of the Ghostbusters to never once be referenced."
• Almost everyone from The Ren & Stimpy Show is completely absent in the Adult Party Cartoon version of the show, except for the titular characters, the Fire Chief, and Mr. Horse. Powdered Toast Man was supposed to come back in a fake commercial called "Powdered Toast Man's Rolling Tobacco," but the show was cancelled before the segment could enter production.
• After the first episode of season six of Recess (the events in said episode were non-canon anyway), Miss Grotke was dropped from the show for unknown reasons. She comes back in Recess: Taking the Fifth Grade, but she ends up being Demoted to Extra.
• Citrocet has a "Gorilla Friend" in The Ripping Friends. He wasn't that much of a main character anyway.
• In Rocket Power, the Rocket's neighbors, the Stimpletons, appear a lot less in Season 3, almost to the point of cameos, actually. Also, how often do you see Mackenzie during that season, either?
• Rocko's Modern Life: Bloaty and Squirmy suffered this fate in Season 4. They'd usually have at least one episode per season, but this was an exception.
• Rugrats:
  • In the original run (1991-94), two slacker teenagers named Larry and Steve were seen from time to time with a different job in every appearance. After the show's hiatus, they disappeared; in a later episode, Larry appeared as a donut salesman — after that, he was never seen again.
  • Tommy's maternal aunt and uncle Ben and Elaine Kropotkin completely vanished from the show after being the focus of two episodes in the original run ("The Wedding Cake" and "Baby Maybe"). Ben got a single nonspeaking cameo at Stu and Didi's anniversary celebration in "The Family Tree", but he and Elaine were otherwise never heard from again.
  • Timmy McNulty and his several brothers. In the early seasons they were set up as friendly rivals for Angelica and the babies. But, after the episode "Wash-Dry Story", they simply ceased to exist.

S

• Scooby-Doo features multiple examples:
  • Scooby-Dum appeared in four The Scooby-Doo Show episodes and as a regular in the Laff-A-Lympics and that was it.
  • After Scooby-Doo and Scrappy-Doo, Fred, Daphne and Velma were absent with no explanation. While Daphne eventually returned to the cast in The New Scooby-Doo and Scrappy-Doo Show, Fred and Velma only made comebacks in The New Scooby-Doo Mysteries as occasional guest stars. It wasn't until A Pup Named Scooby-Doo when Fred and Velma would rejoin Shaggy and Scooby in the spotlight like Daphne had.
  • Scrappy-Doo was last seen in Scooby-Doo! and the Reluctant Werewolf, in which Shaggy had a girlfriend named Googie who's also never been seen again. Well least as a meaningful character anyway. Most whenever Scrappy is seen is usually always as a Take That! for his unpopular status with the fans. His last technical real appearance is as the main antagonist of the first live-action movie where he is arrested after his defeat.
• Lisa Rental, from Sheep in the Big City. She did make a cameo in the Grand Finale, however.
• The Simpsons has featured so many different characters over the years that this was bound to happen more than a couple times:
  • After The Movie and a brief appearance in the opening of the 19th season premiere, Colin was never seen again and Lisa is back to being single. Yeardley Smith actually voiced her annoyance at this, arguing that Lisa deserves "to keep this one."
  • Lionel Hutz and Troy McClure were both retired after their voice actor Phil Hartman's untimely death. Since 1998, they've disappeared from Simpsons canon (with the very occasional exception of a crowd scene). Hutz's role as the Simpsons' incompetent family lawyer is occasionally taken by 'Old' Gil Gunderson, or by the blue-haired lawyer often hired by Mr. Burns. Both characters still appeared occasionally in the comics, however.
  • Dr. Marvin Monroe, who appeared as a recurring character in the first six seasons of the show. In reality, his character was officially retired by the seventh season due to his voice being murder on Harry Shearer's throat. The in-universe explanation given was that Monroe had died, and his tombstone and a hospital named in his memory are seen in the background. He returns in the episode "Diatribe of a Mad Housewife" at Marge's book signing, where Marge is shocked to see he's alive. This trope is lampshaded, with Dr. Monroe giving the explanation "Oh, I've been very sick". He also has a speaking role in "Flanders' Ladder" in Season 29, albeit as a ghost in Bart's dream.
  • Early episodes had two — almost identical — characters called the Weasels do Nelson Muntz's bidding. Sometime around the third season, they disappeared and Nelson became friends with the Jimbo, Dolph and Kearney trio. The producers explained on the DVDs that six bullies felt like too many. They made their first appearance in years in "The Winter of His Content", where it's revealed they moved to Shelbyville.
  • Homer's half-brother Herb seems to be this as well. He made appearances in two early episodes, then never appeared again. The series occasionally will quip about this, such as once when Homer makes a passing reference to "my seldom-seen half brother Herb." Herb makes a speaking cameo on Homer's answering machine in Season 24's "Changing of the Guardian" in which he reveals that he is poor again.
  • The secondary Channel 6 newscaster Scott Christian was quietly phased out after Kent Brockman became recognised as the much funnier character. Ironically, a running gag was suggested that Christian would always be covering for a perpetually absent Brockman, despite the Action News show being named after the latter. One instance of this was trialled in season 1's "Krusty Gets Busted", but was soon rejected, and Brockman does actually appear later in the same episode. Scott did appear a few times in the comics long after he had been phased out.
    • In a similar vein, there's Phil. He was introduced in the Tracey Ullman short "Bart the Hero", but after making a brief appearance in the Season 1 episode "The Call of the Simpsons", he was quickly phased out in favor of Scott Christian and Kent Brockman, and never heard from again (save for a brief scene in "The Springfield Files" where Kent says that Phil, who was demoted to boom operator, was about to be fired; cue Phil hitting Kent with the mic).
  • Serak was in the first Treehouse of Horror along with Kang and Kodos, who appeared in all subsequent Treehouse of Horror episodes, but Serak didn't. This is because "he costs money," being voiced by James Earl Jones.
  • Herman, first seen in "Bart the General", was supposed to be a recurring character, his gimmick being that each time he showed up he'd give a different story of how he lost his arm. Aside from a few cameos, he's never been seen again, and how he lost his arm was resolved in a flashback episode.
  • Bart was originally supposed to have three close friends: Milhouse, plus Lewis, a black kid in an orange shirt, and Richard, an Asian kid with grey hair and a blue jacket. All three are seen hanging around / egging on Bart in a few Season 1 episodes, but then were quickly downgraded to silent background characters as Milhouse emerged as Bart's closest, and basically only friend. Lampshaded in the episode "Das Bus" where Bart confuses Lewis with Wendell (the sickly, curly-haired boy who was also originally intended to be a more prominent Springfield Elementary denizen, but was also downgraded to classroom filler).
  • Lisa's friend Janey is a similar case — in the first few seasons she functioned as Lisa's best friend, then quickly phased out once it became a more defining part of Lisa's personality that she has no friends.
  • Mr. Largo, Lisa's strict music teacher, was limited to cameos after Season 1, as the apathetic Mrs. Hoover emerged as Lisa's main Springfield Elementary foil. Lampshaded in the episode "Homer to the Max" where he walks by as Lisa speaks to Homer about how television shows often phase out characters as the show evolves. Largo eventually returned as a more frequent character around season 15 or so, with a revamped personality that made him more fussy and gay.
  • Sideshow Bob's Italian wife and son disappeared after their second appearance in "Funeral for a Fiend". Bob has appeared several times since, though it is possible that he escaped from prison alone. His mother, actress Madam Underdunk only appeared in that episode, although his father, Dr. Terwilliger did appear once again.
  • Lunchlady Doris suffered this fate in the mid-90s due to the death of her voice actress, Doris Grau. She has since come back in the 2000s thanks to Tress MacNeille, although this character has been retconned as her identical twin sister Lunchlady Dora.
  • Roger Meyers Jr., the head of Itchy and Scratchy studios, had several major roles in the show's earlier seasons before vanishing almost entirely from the series, being one of the most prominent characters on the show to simply disappear. Discounting very rare cameos, he never appeared after "The Itchy & Scratchy & Poochie Show" all the way back in Season 8. His voice actor, Alex Rocco, had died in the interim, making it unlikely for him to return.
  • Ned Flanders and his family live in the house to the Simpsons' right, but what about the house to their left, 740 Evergreen Terrace? In the early seasons it was inhabited by an elderly couple, the Winfields. In the Season 4 episode "New Kid On the Block," they moved out, never to be seen again, and Ruth Powers and her daughter Laura moved in. Aside from that episode (largely revolving around Bart's Precocious Crush on Laura) and the following season's "Marge on the Lam," which heavily featured Ruth, they never made another significant appearance, although Ruth would make frequent cameos in crowd scenes. Ruth's next spoken appearance is in season 14, where Marge refers to her as her "old neighbor" and she mentions that she's been in prison. From there, the house is seen being inhabited by Ruth or is empty and prone to temporary residents Depending on the Writer. In Season 33's "The Wayz We Were," Ruth has this to say about the Simpsons as neighbors:
    Ruth: You haven't stopped by to say hello in 25 years, and I live next door!
  • In "Goo Goo Gai Pan", Selma adopted a Chinese baby named Ling. After various sporadic cameos over the years, she just disappeared after the Season 27 episode "Puffless". It's unclear whether the writers gave up on the character or they couldn't find a new voice actor of the same ethnicity to replace Nancy Cartwright.
  • Maya hasn't been seen or even mentioned since she got engaged to Moe in the Season 33 episode "The Wayz We Were".
  • After the Simpsons adopted her in "The Way of the Dog", the only other appearance of Santa's Little Helper's mother She Biscuit was in the Season 33 episode "Mothers and Other Strangers".
• In The Smurfs (1981), we have Marina the mermaid, Handy's love interest, Gourdy the genie whose master is Farmer and the Pussywillow Pixies...
• South Park:
  • Nurse Gollum from Season 2 and The Movie (other than a voiceless cameo in "Freak Strike"). She was reported missing in one of the video games though.
  • Starvin' Marvin counts as well: he was introduced in the titular episode and was very relevant in early video games and merchandise. He has not been seen since "I'm a Little Bit Country", but continues to appear in most intros.
  • Dr. Mephesto and Kevin. They were main characters in the first 3 seasons, but disappeared early on in the fourth. They both made a one-off apperance in "201" but has not been seen since. Parker and Stone have stated, however, that they grew tired of Mephesto and had wished they'd written him off completely in Season 4. Dr. Mephesto did return in South Park: The Fractured but Whole.
    • "201" also featured Pip making his first speaking appearance in nearly a decade, only to be killed by Mecha Streisand. Word of God said this was because Butters worked better as a Butt-Monkey character.
  • Some of the children's parents that aren't Stan, Kyle, Kenny, Cartman, Butters, Token, Wendy, etc, have been replaced with different people.
  • Midget Wearing Bikini and other joke news reporters seen in the earlier seasons were phased out in favor of just using "Tom" or parodies of actual reporters.
  • Mephesto's son Terrance was introduced as The Rival to the four boys, along with his sidekicks Bill and Fosse. Terrance quickly faded into the background, as did the other two (barring an appearance in the Season 7 episode "Li'l Crime Stoppers"). The three are still occasionally seen as background characters, but lack their signature thick eyebrows. Craig, Clyde, and assorted other boys now play the part of the rivals to the main four.
  • Mr. Wyland, the substitute teacher, though with the logical explanation that Mr. Garrison came back to teaching.
  • Lampshaded in "Cartman's Incredible Gift" when Ms. Crabtree is murdered by a serial killer.
  Lou: "I owe it to that victim over there! I know she hadn't been in any recent episodes, but DAMMIT, she deserved better than this!"
  • Kelly (Kenny's Love Interest in "Rainforest Shmainforest" and "Spontaneous Combustion") inexplicably disappeared after Season 3's "Hooked on Monkey Phonics". In Season 13, it's stated that Tammy Warner is Kenny's first girlfriend so this may be a case of Canon Discontinuity.
    • It should also be noted that Tammy is a One-Shot Character who hasn't appeared in years. The closest thing we ever get to The Bus Came Back was a cameo in Season 16's "Butterballs".
    • However, both Kelly and Tammy were originally supposed to appear in South Park: The Stick of Truth but they were ultimately scrapped.
  • Damien hasn't reappeared in years (aside from background cameos in the gymnasium at times, or being seen on a TV in "Tsst!") despite his father making numerous reappearances.
  • Nurse Goodly (the nurse with no arms from "Cartman's Mom Is Still a Dirty Slut") hasn't made a reappearance in scenes taking place in Hell's Pass Hospital.
  • Fluffy, Cartman's pet pig, hasn't been seen since the episode "Cherokee Hair Tampons" all the way back in Season 4.
  • Speaking of pets, Mr. Kitty, Cartman's pet cat, has barely appeared after Season 3 until she vanished completely from the show after Season 16's "Faith Hilling". She did an appearence in South Park: The Stick of Truth and a cameo in South Park: Phone Destroyer however.
• On Space Ghost Coast to Coast, much of the Council of Doom disappeared without a trace. The most obvious examples are Metallus and Black Widow. Lokar disappeared after "Waiting for Edward", and after "King Dead", Tansut was never seen again.
  • The Creature King suffered this the worst. He was closest thing the sixties series had to a Big Bad. He was the main head of the Council of Doom and fought Space Ghost more times than any other villain. Yet he never appears in Coast to Coast, unless you count stock footage from "Jacksonville".
• Spider-Man (1981) gave J. Jonah Jameson a nephew named Mortimer, who disappeared from the show after the episode "The Hunter and the Hunted".
• SpongeBob SquarePants:
  • Bubble Bass appeared to have suffered this fate, showing up only in the first season before disappearing completely. Apparently he was simply placed on a very long bus ride, because he returned in the Season 8 episode "Plankton's Good Eye" before becoming an Ascended Extra in the next season, getting multiple important roles in seasons 13 and 14.
  • Flats the Flounder, who was the bully at Mrs. Puff's Boating School. He only appeared in three episodes before disappearing. After Season 11's "Squid Noir", he now shows up from time to time as a background character.
  • Squilliam Fancyson hasn't made a single appearance since Season 7, unless you count a very brief reference to him in the Season 10 episode "Code Yellow". Vincent Waller has confirmed that he has no interest in bringing him back.
  • Similarly to Flats, Kevin the Sea Cucumber vanished for ten entire seasons after his role as antagonist in "I'm Your Biggest Fanatic", and finally came back in the Season 13 episode "Patrick the Mailman". He also appears on Kamp Koral.
  • After the movie, the Realistic Fish Head appears very infrequently (being given roughly one appearance per season). He's been increasingly replaced by Perch Perkins (who fills the same role and has the benefit of actually being able to interact with the characters in the show).
  • "Ripped Pants", "MuscleBob BuffPants", and "The Great Snail Race" featured an unnamed announcer character. He was likely replaced by Perch Perkins, but hasn't appeared since season 3.
  • Mr. Krabs' mother, despite making memorable appearances in "Sailor Mouth" and "Mid-Life Crustacean" and having a major role in "Enemy In-Law", has disappeared. She had cameos in "Spongicus" and "Lame and Fortune" and hasn't appeared since.
  • SpongeBob's grandmother disappeared from the show for 13 years for no explained reason, last seen in a "Goodbye, Krabby Patty?" short. Her voice actress, Marion Ross, has since retired from acting, making it unlikely for her to come back. She finally returns in the season 14 episode "Don't Make Me Laugh", complete with a Role Reprise by Ross.
  • Mermaid Man and Barnacle Boy were retired after the death of Ernest Borgnine, who voiced the former, then the death of Tim Conway a few years later, who voiced the latter. Their final speaking appearance was in Season 9's "Patrick-Man!" From there on out, they were only seen in images (e.g. magazines, comic books). They did return in an episode of The Patrick Star Show, where SpongeBob and Patrick travel back in time to see them as babies: and their younger "in their prime" versions show up at the end with speaking roles. Season 13's "SpongeBob on Parade" gives them a silent cameo in person.
  • Patrick's Sister Sam does't appear in the spin-off series The Patrick Star Show, instead in this series, Patrick has a squid sister Squidina. Sam only appears in "Klopnodian Heritage Festival" and "Tying the Klop-Knot" as a background character. Ironically their both existence is a retcon itself since in Season 2 episode "Something Smells", Patrick states that he has no sister.
• Star vs. the Forces of Evil:
  • Pretty much every single Earth character aside from Janna was this after season two, due to the series' shift in focus to Star's home dimension of Mewni. Some of them would later make appearances in season four when Star goes back to Earth for a bit.
  • Jackie Lynn Thomas was a major character in season two, but after her and Marco break up at the beginning of season three, she makes no further appearance until season four's "Britta's Tacos'', where it's revealed she's happily in a relationship with another girl.
  • Alfonzo and Ferguson were introduced as Marco's best (and only) friends in the first episode, and made frequent appearances throughout season one, even going on an adventure with the two in one episode. Starting in season two, the duo completely vanished outside of a brief cameo of their arms in a crowd, with Star herself even pointing out their absence. Likely justified, as the show's creator hated them and only included them due to the network's demands.
  • Brittany and Jeremy were introduced as rivals towards Star and Marco respectively and would oppose them frequently throughout season one. They had much less appearances in season two, before vanishing completely by season three.
  • Some minor characters that were antagonists in early episodes such as Gustav, Monster Arm, and Lobster Claws never made another reappearance after their respective episodes. Lobster Claws at least appeared in another episode and was the focus of one of them, but he never showed up again afterwards.
• While many characters from the Clone Wars multimedia project made it into the 2008 Star Wars: The Clone Wars, a few that were planned to appear were scrapped. ARC Clone Trooper Alpha was replaced with newcomer Captain Rex ^note mainly to avoid unintentional aliteration when there were a few A-names in the main cast. Meanwhile, bounty hunter Durge was a major antagonist in previous installments, including Genndy Tartakovsky's Star Wars: Clone Wars shorts. He was briefly reimagined for early drafts of "Hostage Crisis", but was replaced by Cad Bane, who became the Separatists' chief mercenery for the rest of the series.
• Static Shock: The Season 2 episode "Pops' Girlfriend" introduces us to Robert Hawkins' new girlfriend, police officer Trina Jessup, who only appeared in 2 episodes and never made a single appearance in the third and fourth seasons.
• Strawberry Shortcake: A character named Plum Puddin' accompanied the titular protagonist in her adventures since his debut and was a major character. Plum failed to make it very far into the series, with his place being taken by a girl of the same name who inverts the trope.
• Superfriends:
  • The Super Friends' teenage sidekicks Wendy and Marvin and their pet Wonder Dog vanished from the franchise after the original 1973 series, with the remainder of the continuity replacing them with the Wonder Twins and Gleek.
  • The Wonder Twins and Gleek themselves as well as most of the cartoon's Captain Ethnic Canon Foreigners were subjected to this later on, with Samurai being the only character created for the series who returned for the final series The Super Powers Team: Galactic Guardians.
• In SWAT Kats, we have a couple of examples. In all cases, the characters are likely still there, somewhere in Megakat City, but just never focused on.
  • Feral's second-in-command Steel. He is last seen being chewed by Feral in "Enter the Madkat", and never reappears in the second season. It's been argued that Feral's niece, Felina, replaced Steel as her uncle's second in command, however they have different ranks and uniforms — Felina is only a lieutenant and Steel was a lieutenant commander.
  • Burke and Murray. Last seen briefly in "Metal Urgency", they are never seen or mentioned again. The main reason for this seems to be the lack of any scenes focusing on Chance and Jake's civilian lives in the second season, and since Burke and Murray were created to antagonize the two in those scenes, when they went, so did Burke and Murray. The two were slated to appear in an episode that never got made, though.
  • Al the Kat's Eye News helicopter pilot. He's last glimpsed in a non-speaking role flying the copter in season one's Chaos in Crystal, and although the helicopter itself appears multiple times in many other episodes, Al himself is never seen again. However, considering someone has to be flying the aircraft, he is probably still there.
  • Dr. Street is last seen getting knocked out of a window in The Ci-Kat-A. He presumably could've saved himself by using his wings to fly to safety, and, indeed, this was what the writers had in mind, as they wanted him to return in another episode and team up with Dr. Viper, but the series was cancelled before the episode was finished.
  • Dr. Viper himself. After turning himself into a giant monster in Mutation City, he gets doused with anti-mutagens and disappears from both the episode and the series. His final appearance is in The Origin of Dr. Viper, but that's told entirely in flashback. As mentioned above, though, he was scheduled to reappear in an episode alongside Dr. Street, but then the show was cancelled.
  • Bizarrely, the SWAT Kats' own arch-enemy Dark Kat. He gets away at the end of Razor's Edge in season two, vowing to return, but apart from an alternate universe version of him in The Dark Side of the SWAT Kats and a cameo as a cardboard cutout in The Origin of Dr. Viper, he never reappears, nor do any of the known unfinished episodes involve him.
  • In an example of Early-Installment Weirdness, there are a lot of reporters besides Ann Gora seen in The Giant Bacteria, including two male reporters from Kat's Eye News and two from a different news channel called Inside Megakat City. Both male Kat's Eye News reporters get to interview Feral in two different scenes, but after this episode, neither they nor the other reporters appear again. Inside Megakat City vanishes and Kat's Eye News is apparently the only news channel of any importance in town, and, aside from one brief appearance by Tab Mouser (who vaguely resembles one of the reporters from The Giant Bacteria) in Unlikely Alloys, Ann Gora appears to be its only reporter!

T

• Teen Titans (2003):
  • In the first episode, arch-villain Slade is always seen with a silent butler standing at attendance — possibly Wintergreen, Slade's butler in the original Teen Titans comics. He is never seen with Slade after this episode, but if you look quickly, he is seen with the Brain's group of villains in the final season. (Word of God says that Slade was uninterested in joining, but sent Wintergreen as his representative.)
  • The H.I.V.E. Academy Headmistress was initially shown as the one training teen supervillains at H.I.V.E. Academy. When the H.I.V.E. organization resurfaced in later seasons, she had been usurped by Brother Blood with no real mention of what happened to her. She returned in the series finale as part of the big final showdown but was quickly dispatched. She later appeared in the comic alongside a new trio of teen villains, but was quickly Bound and Gagged by Robin and presumably arrested. In all of this, it was never explained exactly what had happened that lead to her being booted from her position at the academy.
  • In the final season, the Brotherhood of Evil recruits nearly every villain that ever appeared in the series (including some who were in no condition to do such). Some, such as Bob and the Nufu alien, show up in the initial lineup, but are never seen fighting the Titans.
  • At the end of "Homecoming — Part 2", the Doom Patrol parted with the Titans, claiming they would continue chasing after the Brotherhood of Evil (who had been their enemy up until that point). Then the Brotherhood put their full efforts targeting the Teen Titans and other younger superheroes, and the Doom Patrol are nowhere in sight, the Titans never try to contact them, and no one even directly mentions them.
• In the original Teenage Mutant Ninja Turtles cartoon there was an episode involving a female lizard mutant named Mona Lisa. She serves as a potential girlfriend for Raphael and helps him fight off hijackers who were responsible for her mutation (she was originally a human); at the end they say their goodbyes and she secretly follows Raphael and April to the turtle's lair and introduces herself to the rest of them. Despite this being a setup for her being a recurring character and being a fan favorite she is never seen or mentioned again.
  • That cartoon used to pull the same schtick all the time. They'd have an episode that seemed to set up a new cool character, then they'd usually disappear forever. Remember Metalhead? And Muckman and Joe Eyeball?
  • Several notable recurring characters, some of which had been on the show from the beginning, just disappeared during the show's 7th and 8th seasons. Season 7 saw the final appearances of the friendly teenage aliens the Neutrinos and the Turtles' young friend Zach. In season 8, Irma, Vernon, Mr. Thompson, and Casey Jones made their last appearances and then vanished without explanation. Bebop and Rocksteady disappeared after season 8, even failing to appear when Shredder and Krang returned for a story arc in the final season with no explanation for the bumbling duo's absence.
• In Teenage Mutant Ninja Turtles (2012), the character of the Pulverizer/Timothy/Mutagen Man had completely disappeared from late season 3 onward. Despite Donatello promising to turn him back into a human, he's not even given a passing mention when Donatello creates the Retro-Mutagen. And is never seen (not even as a background cameo) or spoken of ever again.
• Thomas & Friends:
  • After the rights to were acquired by HIT Entertainment, and some of the original producers left the show, several semi-regular characters, such as Duck, Oliver, Boco and Daisy, were dropped in order to focus on the Steam Team. This also happened to several one-off and recurring original characters that were made as an excuse to make and sell more toys. Season 17 and onwards, however, reinstated some of them them back into the series after Andrew Brenner took over as head writer, with Duck, Bill & Ben, and Harvey re-appearing in season 17 in prominent and respectable roles, Oliver and Toad in season 18, and Daisy and Donald & Douglas in Sodor's Legend of the Lost Treasure.
  • This trope also applies to Logging Locos, whose main entrance way into Sodor was purportedly seen boarded up in several episodes without any explanation. Their only reappearances were a single eighteenth season cameo by Ferdinand, and several learning segments.
• Timon & Pumbaa: Though most of the characters from the movie made at the very least a cameo in the series once (even Scar did at one point under the name "Claudius", and Simba appears as an adult in four episodes), Nala and the other lionesses weren't in a single episode, though they did return in the sequels.
• Todd McFarlane's Spawn has Angela, who is a very popular character with many arcs in the comics, shows up in Season 1. She even has an Establishing Character Moment, when she beats up a group of thugs in an alley after attempting to kidnap her at knife point and rape her. She protest not being able to hunt the latest Spawn to her superior.. and that's it, her scene ends and we never see her again. She was supposed to show up again in Season 3 as the hunter trying to kill Spawn, but she was replaced by a series exclusive character named Jade instead.
• The Transformers:
  • Over time, several characters from the first and second seasons stop appearing after the movie and later seasons in order to focus more on the new characters. Having a huge cast in a Merchandise-Driven show, it's easy to forget and lose track on who's who. This meant characters who actually survived the film, such as Grapple, Sunstreaker, Hound, Jazz, and Cliffjumper, disappeared into thin air and reappeared in the realm of fanfiction forever. Put simply, if your toy wasn't on the shelves at the time (or was relegated to being a mail-away offer) you were liable to simply cease to exist without a word.
    • There is a bit of an explanation behind Cliffjumper, though: Cliffjumper's voice actor, Casey Kasem, left the show due to disgust over the fictional nation of Carbombya (Kasem was of Lebanese descent).
  • Skyfire was a particularly early sufferer, given that he was Screwed by the Lawyers: after redesigning him to the point that he no longer resembled his toy and even changing his name, the show bible actively advised the writers to not use him again. As a result, he completely vanished after the 25th episode, despite being one of the largest and strongest Autobots, and at the time, one of the only ones capable of spaceflight.
  • The third season was even more confusing to Japanese viewers, because The Transformers: The Movie wasn't released in Japan until 1989 (by comparison, it was released in the United States and Europe in 1986). This meant that characters who died in the movie such as Prowl and Wheeljack were alive and well in the Japanese-exclusive series.^note Or they did die and were replaced by alternate selves from another universe, as described in various Japanese sources... yeah, it's complicated.
  • Other dead characters such as Huffer, Brawn, and Windcharger also appeared via animation errors in the third season. Then you have characters whose deaths were scripted, but never animated (such as Trailbreaker, Smokescreen, Red Alert, and Shockwave), making it ambiguous if they too survived or not.
  • Even disregarding all of that; Laserbeak, despite surviving the movie, notably disappears from the series after a brief cameo in Season 3's "Webworld" without a single explanation, following in the footsteps of Rumble. Buzzsaw and Frenzy, their respective Palette Swaps, also vanish after the Movie with nary an excuse.
• The human villains who served as recurring antagonists for the first and second seasons of Transformers: Animated are absent from the third. Only The Headmaster returns for the season premiere and that's all.
• Fracture and his Mini-Cons disappear in the first season of Transformers: Robots in Disguise (2015) and a series of shorts which is odd as the rest of Steeljaw's pack continue to make appearances.
• T.U.F.F. Puppy:
  • Earlier episodes featured members of D.O.O.M. other than Snaptrap, Francisco, Ollie and Larry who were mainly limited to background roles, such as the Mole, Bad Dog and Leather Teddy. They were nowhere to be seen after season one.
  • "Lucky Duck" shows Quacky to have other cohorts/co-stars besides the Sharing Moose, such as the Counting Cougar and the Phonics Fox. In all subsequent episodes, the Sharing Moose is the only one of them still shown to be working for Dudley, with the only acknowledgement of Quacky having other minions being the Quacktion Figures bearing their likenesses that are used for Quacky's scheme in "Quack in the Box".
• The Loud House
  • Coach Pacowski hasn't appeared in the series since season 5.
  • Leni's boyfriend Chaz hasn't been mentioned since the season 3 episode Really Loud Music.
  • Agnes Johnson, Principal Huggins and Mick Swagger weren't seen or mentioned once in season 7.
  • Since The Casagrandes have ended, The Changs haven't appeared or been mentioned since then. Sid, however, did appear in The Casagrandes movie.
  • Lincoln and Clyde's favorite band Smooch haven't been seen since season 2.
  • Lisa's former teacher Ms. Shrinivas hasn't appeared since season 4. She didn't even bother showing up in Save Royal Woods! which pretty much every character appears.

U

• Ultimate Spider-Man
  • Mary Jane Watson mysteriously disappeared after Season 2. She finally came back in season four as the Carnage Queen.
  • J. Jonah Jameson pretty much disappears in Season 4, only appearing in two episodes.
  • Due to the Fox embargo mentioned in the Avengers Assemble entry above, characters like Wolverine and Doctor Doom stopped appearing midway through Season 3. It was especially notable during the four-part adaptation of Contest of Champions (1982), which despite bringing back a huge number of heroes and villains from past episodes, neglected to include any of the X-Men or Fantastic Four-related characters Spidey had previously encountered.
  • Deadpool only shows up for one episode in season two and is never seen again after that. His movie being R-rated, coupled with the aforementioned Fox embargo, likely contributed to his lack of future appearances.

V

• VeggieTales: A number of early appearing characters gradually bowed out as the series went on:
  • Pa Grape, who remains a mainstay on the cast to this day, originally had an entire family, consisting of himself, Ma Grape, and their two kids Tom and Rosie, who were introduced alongside him in "God Wants Me To Forgive Them?!?". Tom was arguably the luckiest out of the family members; showing up with voiced roles up to "Josh and the Big Wall" before dropping off the map. Ma arguably made an appearance in "Abe and the Amazing Promise" playing Sarah opposite Pa as Abraham (though her appearance and voice was pretty far removed from how she looked back in the show's early years), but has otherwise had no other major roles in the series since her debut episode. Rosie was the unluckiest out of Pa's family, only making voiceless cameos following her debut up to "Larry-Boy and the Fib From Outer Space" before vanishing entirely. When the plot of The Pirates Who Dont Do Anything A Veggietales Movie called for Pa's character to have a family, new characters were created instead of bringing back the original characters.
  • Lovey Asparagus, a recurring minor character who often played Archibald's Love Interest/wife, last appeared in a very easy to miss cameo in Jonah: A VeggieTales Movie before getting dropped from the series as well.
• This may be the fate of Vehicle Voltron in all Voltron shows post the original 1984 series. They don't get so much as a shoutout in either The Third Dimension or Voltron Force. Possibly it's a reflection of the lack of popularity of the Dairugger XV derived segment and World Events Productions' reluctance to spend money retaining the rights to it.
• Subverted with Kaltenecker in Voltron: Legendary Defender. The team got her in a Breather Episode in season two and she was never seen again...until season four, when she shows and from that point on pops up occasionally, mostly for comic relief.

W

• The Wacky Adventures of Ronald McDonald:
  • The Fry Kids make no appearances whatsoever after the first video "Scared Silly".
  • Tika disappears after the fourth video "Birthday World".
  • Franklin and his father Dr. Quizzical make their final appearances in the penultimate video "Have Time, Will Travel", receiving not so much as a mention in the final video "The Monster O'McDonaldland Loch".
• The Wild Thornberrys had a pair of minor recurring villains named Kip O'Donnel and Neil Biederman, a pair of poachers who occasionally antagonized the titular family. While they were featured in the pilot episode, presumably to establish them as the main antagonists, they only made seven appearances in the main series before disappearing completely after the second season.
• Winnie the Pooh: Gopher has all but disappeared from the franchise since the 2000s, last appearing in Pooh's Heffalump Halloween Movie, and that was via recycled footage from Boo to You Too! Winnie the Pooh. Tellingly, his return appearance alongside the rest of the Winnie-the-Pooh cast in Kingdom Hearts III was met with genuine surprise from both the Kingdom Hearts and Pooh fanbases, and even then he still has yet to reappear in any explicitly Pooh-oriented media.
• Roy from Winx Club. He appears in early season 5 as an old friend and potential love interest for one of the main characters, Aisha, after the death of her previous lover. Roy is shown to have some chemistry with Aisha, and she shows romantic interest in him in season 5. However, in season 6, a rival appears, sparking a Love Triangle where both boys literally compete for her affection. The newcomer is ultimately declared the winner midway through the season and Roy disappears with absolutely no explanation. He is never mentioned again.

X

• X-Men: Evolution: After the rise of Apocalypse, Sabretooth just disappears from the show. While it's given a small Hand Wave courtesy of Pyro (claiming he was 'playing with a ball of yarn somewhere'), it's more of just Pyro rambling and doesn't mean a thing. Similarly, Destiny disappears in season 3 without any mention. When she last appeared she tells Mystique that she'll be involved in a plot to bring back an ancient mutant, but by Mystique's next appearence, she's working with Mesmero to bring back Apocalypse without any mention or reason.

Y

• In the Yogi Bear TV movie “Yogi’s Great Escape” three orphan bear cubs named Bitzy, Buzzy, and Bopper are dropped off at Yogi’s door step, at the end he and Boo Boo decide to adopt them and they declare them their honorary uncles, despite this the trio are never seen again, several Yogi Bear movies and specials were made afterwards and they are nowhere to be seen.

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