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Trilogy Creep - TV Tropes

️Mon Jan 14 2008

The strange tendency of trilogies to expand and see more and more works added to The 'Verse. This is mainly found in books, but has also happened frequently with movies, and can occur with any other type of media as well.

Science Fiction author Orson Scott Card has suggested that this is the result of Executive Meddling; rather than allow an author to just write the books they want to write, publishers pressure them into producing sequel after sequel in order to take advantage of the preexisting fanbase and milk a Cash-Cow Franchise bone-dry.

Two-Part Trilogy is somewhat related, typically the result of a one-part story expanding into a trilogy. Contrast Divided for Publication, which is when a work is split into more parts than the author originally envisioned, due to excessive length, and Divided for Adaptation, which is when a work, particularly if it's the final book in the series, is split into two or more parts in an adaptation.

See also Franchise Zombie and Sequelitis. Capcom Sequel Stagnation is a related trope for Video Games.

Example subpages:

Literature

Other examples:

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Anime & Manga

Originally, the Rebuild of Evangelion series was to be two individual features followed by two shorts packaged together as a third "film". After the resounding success of 2.0, however, plans apparently changed and 3.0 and 3.0+1.0 were both expanded and made into feature-length movies themselves.

Audio Plays

In the Big Finish Doctor Who "Companion Chronicles" series, "Echoes of Grey" and "The Memory Cheats" were supposed to be the first two parts of a trilogy. The CD notes for the third instalment, "The Uncertainty Principle," make it clear that it is not the planned final part, and the 'trilogy' is now expected to be four episodes long.

Comic Books

Kick-Ass was supposed to be three issues, which then changed to four by the second issue; then it was eight. By the time it ended the comic was now a trilogy consisting of three volumes comprising eight, seven and eight issues respectively, as well as a five-issue Hit-Girl miniseries. And then the franchise was rebooted with a black female protagonist.
Runaways was originally going to be a single miniseries, but the series' success caused Brian K. Vaughan to create an ongoing, which was supposed to end with a run by Joss Whedon, but instead led to a third series, a slew of guest appearances and event tie-ins, a new, In Name Only incarnation, and Nico Minoru and Victor Mancha getting promoted to off-shoots of The Avengers.
The Chilean comic Zombies en la Moneda, by Mythica Ediciones, was originally planned as a trilogy, and the third volume presented a satisfactory ending, however its great popularity motivated to create a sequel also in the form of a trilogy, moving the action from Santiago - the capital of Chile- to Valparaíso, the main port of the country. There were plans for a sequel (where the zombies would invade The White House) and spin-off, but the death of Marco Rauch, founder and owner of Mythica Ediciones, has put all these plans in doubt.

Fan Works

In the case of The Calvinverse, this happened to two different trilogies at the same time - Swing123 and garfieldodie both made their own separate Calvin and Hobbes trilogies, and ultimately Retro Chill served as a crossover between the two (cementing the series as a universe, it could be said).
The Elemental Chess Trilogy of Fullmetal Alchemist stories was originally exactly that, but has been expanded to include a Prequel, a Distant Finale, and a collection of side stories. Despite this, it's still called a trilogy.
Phoenix Wright: Ace Attorney: The Contempt of Court originally inverted this but ended up playing it straight. The game was planned as four cases: "Turnabout Scapegoat", "The Haunted Turnabout", "Turnabout Before A Fall" and "Turnabout of the Snow". "Before A Fall" ended up being cut, condensing the story to three cases... but "Turnabout of the Snow" ended up so long it was split into two cases, its second half becoming "The Ensnared Turnabout".
Turnabout Storm is an interesting case. Originally a 4-part series, the episode count increased to five when Part 3 was split into two episodes via Simultaneous Arcs, but with the final part still being called Part 4 — At least until Part 5, the real conclusion, was confirmed via Cliffhanger.
XCOM: The Hades Contingency, as well as its sequels, were originally intended to be a trilogy. However, Advent Directive, the third story, proved itself to be so big that its final acts had to be split into a fourth book..

Films — Animation

Toy Story 3 seemed like a fitting conclusion to a beloved franchise, providing the closure that every fan wanted. Everyone expected it to be the grand finale to the series. But then, nine years later... hello Toy Story 4! And if you thought that was the end... Surprise! Toy Story 5 is slated to release in 2026.
For a long while, Wallace & Gromit consisted strictly of three short films: A Grand Day Out, The Wrong Trousers, and A Close Shave. Many years later, there would be a full-length fourth entry, The Curse of the Were-Rabbit, as well as a fifth short film, A Matter of Loaf and Death.

Films — Live-Action

Alien³ is the definitive ending for the story of Ellen Ripley, who died by simultaneously falling into molten lead and giving birth to a Xenomorph queen. However, Alien: Resurrection brought the character back as a clone who finally made it to Earth. Up until the release of the Alien Legacy box set in 2000, the first three movies were still packaged in one case as the "Alien Trilogy", with the fourth film packed in separately. It's also been released as a "Quadrilogy"^note and an "Anthology" (to say nothing of the spinoff Alien vs. Predator films or the prequels Prometheus and Alien: Covenant).
The third All Night Long film had the subtitles The Final Chapter and The End. It was followed by All Night Long R, All Night Long O, and All Night Long 6.
The American Pie trilogy, direct-to-video spinoffs aside, later got a fourth movie: American Reunion. A fifth movie has been stated to be likely.
The Bourne Series was seemingly a full-circle trilogy... until a Spin-Off fourth installment, The Bourne Legacy came out in 2012. Then a fifth film, Jason Bourne, came out in 2016 by the same team as the first three films (minus scriptwriter Tony Gilroy).
Deadly Dares: Truth or Dare Part IV, made thirteen years after Screaming for Sanity: Truth or Dare 3.
The Diary of a Wimpy Kid movie trilogy was based on the first four books, with the third movie combining elements from the third and fourth books and taking the title of the fourth book. Five years later, The Long Haul, based on the ninth book, was released with an entirely new cast. Later, 3D-animated movies would be released on Disney+, each based on the first, second and sixth books.
J.K. Rowling's Fantastic Beasts and Where to Find Them was initially announced as the first in a trilogy, then bumped to five films right before it released. Rowling says the trilogy announcement was a placeholder while she was still working on the series' outline and before she’d nailed down the firm number. Ultimately subverted, as the poor performance of Fantastic Beasts: The Secrets of Dumbledore led to the franchise being shelved.
The Indiana Jones trilogy was expanded with a fourth movie after a nineteen-year hiatus. Justified in that the Indiana Jones series was originally intended to be five or six movies long anyway, but things just kept getting in the way of development. In the meantime, much material was added to the Expanded Universe. A fifth movie would then happen, but with only Harrison Ford left.
Ip Man 3 was initially intended to be a trilogy capper for the Ip Man film series, with a spinoff without the title character (Master Z: Ip Man Legacy) coming out after it. Then Ip Man 4 was announced, and Donnie Yen was paid a hefty sum to return, seemingly for the last time.
George A. Romero's Living Dead Series. The original Night of the Living Dead (1968), Dawn of the Dead (1978) and Day of the Dead (1985) stood as a trilogy for 20 years and became a hallmark of the zombie film genre before receiving a fourth installment in Land of the Dead, which got some great reviews but was viewed by some fans as a disappointment. Two more installments, Diary of the Dead and Survival of the Dead, came out in rapid succession, to very little cultural impact.
Mad Max was a trilogy for 30 years — and then came Mad Max: Fury Road, which even required a change of lead actor and filming location. George Miller has stated it will start a whole trilogy.
Marvel Cinematic Universe:
- Thor is the first character to headline more than three solo films, with Thor: Love and Thunder being the fourth. Though Thor: Ragnarok found a solid ending for his arc, the Happy Ending Override from Avengers: Infinity War means he's at the start of a new arc.
- A variant: Captain America: Brave New World is technically the fourth Captain America movie. But it's not the same character, as Sam Wilson/Falcon has taken the mantle and shield of Steve Rogers, so this movie serves more as a sequel to the The Falcon and the Winter Soldier miniseries.
The Matrix:
- The Matrix Revolutions concluded the Matrix trilogy... then a fourth film, the rather aptly titled Resurrections, was ordered over 15 years later.
- Resurrections is also metafictional, and features Neo as a game developer whose "beloved parent company Warner Bros." is forcing him to make a sequel to his successful trilogy.
The Omen series initially ran for three films that were released between 1976 to 1981 with the third being billed as the last of the trilogy. A fourth film though was released in 1991 (although, unlike the previous three, it was a TV movie).
After a trilogy, Paranormal Activity came out with a fourth film in an obvious attempt to get more money from the fans, followed by Latino-focused spinoff, and apparently finished with The Ghost Dimension. Then in 2019, a seventh film was announced.
Pirates of the Caribbean. However, the fourth film is an entirely new adventure featuring Jack Sparrow, rather than a continuation of the previous films' arc. A fifth film was later made which was more connected to the original trilogy than its predecessor.
The modern Planet of the Apes trilogy (Rise of the Planet of the Apes, Dawn of the Planet of the Apes, War for the Planet of the Apes) saw a fourth film that would have initially been a Continuity Reboot, Kingdom of the Planet of the Apes.
Rambo (2008) arrived in theaters a full two decades after the final installment in the original First Blood trilogy that introduced the character to movie audiences. The fourth film isn't really that gratuitous, however, since it allows John Rambo some closure by having him, at the film's very end, finally return to his father's ranch in Arizona, which he has been away from for close to 40 years.
The Saw franchise is easily one of the largest examples of this trope.
- To put it through: Saw was originally intended to be a standalone film. Because of its astounding success, the creators decided to make two sequels in order to finish with a trilogy. Due to Executive Meddling after the larger success of those movies, they came back after the third one and just decided to flesh out a story and keep writing until they came up with the perfect ending. They came up with an additional 5 movies, but due to further meddling they had to condense the last two into Saw 3D, which would have originally ended the franchise in 2010. However, it was revived in 2017 with Jigsaw, with a ninth entry, Spiral, being later released in 2021.
- According to Darren Lynn Bousman, the director of Saw II, III, IV and Spiral, there are currently five more movies in development, which include two direct follow-ups to 3D (with the Working Titles Saw IX and X), a direct sequel to Jigsaw, and two sequels to Spiral, which is also set to get its own TV series.
One of the taglines for Scary Movie 4 was "The Fourth and Final Chapter of the Trilogy"... Then Scary Movie 5 came out. In France, Scary Movie 3 had the tagline "Best trilogies are in three parts."^note For that matter, it wasn't even the first time they had pulled such a stunt. One of the taglines for the original Scary Movie was "No shame. No mercy. No sequel." One of the taglines for the second film was "We lied."
Scream 4, though given that this is the Scream series, it took a couple digs at this.
Spy Kids. However, the film is not really a continuation of the first three, since it's centered around a new family (the family of the previously unmentioned aunt of the original spy kids, to be exact), though the original spy kids, now grown-up, do appear.
Star Wars: The Original Trilogy (Episodes IV-VI, formerly referred to as the "Star Wars Trilogy") was later expanded with a new "Prequel Trilogy" of movies (Episodes I-III), as well as multiple television series, games, books and comics in spin-off material. Though many had believed the saga was completed with Revenge of the Sith in 2005, a new "Sequel Trilogy" (Episodes VII-IX) went almost immediately into production following Disney's acquisition of Lucasfilm in 2012 (getting finished in 2019), as well as new spin-offs. Justified in that Star Wars was not originally intended to be just a trilogy, with initial plans aiming for a twelve-movie saga including prequels and sequels. Then George Lucas shortened to nine following the first movie, and settled on six after the second.^note
The Transformers Film Series met a fitting conclusion with the third film: Transformers: Dark of the Moon, with all Decepticons dead and the Autobots accepting Earth as their new home. But it made so much money they ended up making Age of Extinction and The Last Knight.
The View Askewniverse, which started out as the New Jersey Trilogy. There are eight films released as of 2023.
The credits for Violent Shit III: Infantry of Doom read "End of Trilogy". Cue another sequel, Karl the Butcher vs. Axe, eleven years later.

Live-Action TV

Kamen Rider Den-O's third movie was explicitly called "Farewell Kamen Rider Den-O: The Final Countdown", and features a Passing the Torch aspect with the introduction of a new Den-O, and on a meta level it was believed to be the end of the series because star Takeru Satoh was moving on to other roles. Another three / five Den-O movies^note have come out since then. Possibly lampshaded in the DVD release of "Final Countdown", where a short extra cartoon has one character remark that, for all the talk of "final" and "conclusion", that doesn't stop them from making more sequels.
For some reason, CBS advertised the Person of Interest episodes "The Cold War", "If-Then-Else", and "Control-Alt-Delete" as a trilogy, but the next episode "MIA" is a key part of the arc.

Music

Played straight and subverted by Bad Religion, where Part III received a sequel and a prequel on the album 'Suffer' in Part II (The Numbers Game) and Part IV (The Index Fossil), but no Part I. Brett Gurewitz, when asked by a fansite, cited Big Bang as the closest to Part I that he could think of.
Rush:
- The song "Where's My Thing?" is described as part IV of the Gangster of Boats trilogy. There kinda actually weren't any Gangster of Boats songs before it.
- Played straight with "Freeze (Part IV of Fear)" from Vapor Trails. Fear is a "trilogy" that was released in reverse order with Part III, "Witch Hunt," from Moving Pictures first and Part I, "The Enemy Within" from Grace Under Pressure released third.
When Secret Chiefs 3 released Book of Horizons in 2004, Trey Spruance said it was the first part of the "Book of Truth" trilogy. The very next part wound up split in two: Book of Souls: Folio A (released in 2014) and Book of Souls: Folio B (which as of June 2019 still hasn't come out). A proper third part is still planned as well, meaning the finished "trilogy" will actually be four albums, at the very least.

Theatre

It is believed by some scholars that William Shakespeare wrote the three Henry VI plays out of sequence: first Part II, then Part III, then finally Part I. Moreover, from a critical and performing standpoint, they are often lumped together with Richard III as an overall "Wars of the Roses" story.
Though Der Ring des Nibelungen was not originally conceived as a trilogy, it was already four plays by the time Richard Wagner began composing the music, and is not commonly thought of as a trilogy, its official heading being "a stage festival play for three days and one evening before."

Video Games

Atelier Series:
- In 2009, Atelier Rorona: The Alchemist of Arland was released. The next year, its sequel, Atelier Totori: The Adventurer of Arland, came out, followed by Atelier Meruru: The Apprentice of Arland to finish the trilogy. The next Atelier game to be released was Atelier Ayesha: The Alchemist of Dusk, which is set in a new continuity. Once the Dusk and Mysterious trilogies had concluded, a fourth game set in the Arland continuity was announced: Atelier Lulua: The Scion of Arland. That said, although Meruru had indeed been originally planned as a trilogy closer, its director had admitted that the ending hadn't been very conclusive and that there was room to do a proper one sometime, so the only thing that really sticks out about Lulua is the amount of time it took after Meruru for a fourth game to happen and the style shift that came with it.
- And again in 2022 with the release of the fourth game in the Mysterious trilogy (after two games in the Ryza/Secret series): Atelier Sophie 2: The Alchemist of the Mysterious Dream.
After Another Century's Episode 3: The Final came out, many people were hoping for a new A.C.E. game would be released sometime. Lo and behold, Another Century's Episode: R for the PlayStation 3. Note, however, that it is more or less a new continuity as opposed to an actual story continuation. Incidentally, Director Terada more or less said, "I don't know why we called A.C.E.3: The Final (due to them apparently having every intention of making a new game). So, let's just say that A.C.E.3 was "The Final PlayStation 2 A.C.E. game."
Apollo Justice: Ace Attorney, the fourth game in the Ace Attorney series. Shu Takumi had planned the series to be a trilogy, but Capcom called for another game. The protagonist change was due to the fact that the former three games already told all the stories for Phoenix. Ace Attorney Investigations was meant to be a Gaiden Game, with a fifth game in the main series planned. Investigations ended up getting its own sequel before Dual Destinies was released, though Investigations 2 was Japan-only until it saw a worldwide release in 2024 as part of the Ace Attorney Investigations Collection.
From 1988 to 2015, The Bard's Tale Trilogy was accurately known as "The Bard's Tale Trilogy." Then InXile announced that work had begun on The Bard's Tale IV.
A very particular case of this occurs in Rocksteady Studios' Batman: Arkham Series. The series was originally intended to be a trilogy — the first game being Batman: Arkham Asylum, the second game being Batman: Arkham City, and the third and final game being Batman: Arkham Knight. However, Warner Bros. Montreal (who developed the Wii U port of Arkham City) released a prequel to Asylum called Batman: Arkham Origins between City and Knight to hold fans over until Knight was released. And that's not counting the various spin-off mobile games or Batman: Arkham Origins Blackgate.
When Fabula Nova Crystallis was conceived, it was originally meant to consist of three self-contained games that shared one mythology. Nine years later, and it jumped to six games and about three or four short stories, with possibly more coming along the way.
While there was never really a stated number of games planned in the Five Nights at Freddy's series, Five Nights at Freddy's 3 seemed like it was being built up as the end of the series, what with the game being set thirty years after the first one, featuring only a single surviving animatronic (maybe), and ending with the Purple Guy finally being killed off by the spirits of the very children he murdered and then forced to haunt a robot like them, the kids' spirits moving on to the afterlife, and the pizzeria burning down at the end, seemingly putting an end to the Fazbear nightmare. Then a fourth game was confirmed, and was definitively billed as "The Final Chapter"; the game itself supported this, ending by what seemed to be The Bite of '87. After this, no further games seemed incoming (aside from the largely non-canon spin-off), and Scott Cawthon was absolutely adamant that the series was over and there would be no further sequels... until a fifth game was announced, with Cawthon explaining on Steam that "I never said I couldn't change my mind." He trolled even further by disguising the sixth game as another spin-off, but also made that look like the Grand Finale by having the main villain and a number of animatronics burned alive. But then Five Nights At Freddys VR Help Wanted and Five Nights at Freddy's: Security Breach came out... And that's not counting all the novels.
Halo is an interesting case, as Bungie originally planned for it to only be two games; Microsoft wanted a third game and development time for Halo 2 ran short, so they stretched it out over Halo 2 and Halo 3. Then there's the interquel Halo 3: ODST (planned, but expanded) and the prequel Halo: Reach (never planned), which roughly fit into the same "trilogy". In 2012, Halo 4 was released, stated to be the beginning of a second trilogy, called "The Reclaimer Saga", with 343 Industries as the developers. The final game in the Reclaimer Saga would be Halo 5: Guardians, before the trilogy was abandoned with the release of Halo Infinite, which incorporated more elements from Bungie's titles.
Both "Hitman Trilogy", a boxset for the PS2, and "Hitman HD Trilogy", a similar set for the PS3 and 360, actually feature the second, third and fourth entries in the Hitman series (Silent Assassin, Contracts and Blood Money), skipping the original game in the entirely. The original game in the series, Hitman: Codename 47, was a PC-exclusive; not to mention Contracts is, in effect, a remake of it.
Jak and Daxter was originally intended as a trilogy and thus was written as such: at the end of the third game, the Precursors are revealed and the Big Bad is defeated. However, a racing spin-off was released a year later, followed by a PSP game with Daxter in the lead, and a PS2/PSP game developed by a different team than original creator Naughty Dog.
Kingdom Hearts had one game come out between parts I and II. There were six more complete titles released between II in 2005 and Kingdom Hearts III in January 2019 — and while III serves as the Grand Finale for the "Dark Seeker Saga", it still left open just as many questions as any other entry, ensuring that this "trilogy" of eleven games wouldn't be over any time soon, eventually resulting in Kingdom Hearts IV.
Kirby actually manages to invert this (by also using a variation of Two-Part Trilogy): You've got Kirby's Dream Land, Kirby's Dream Land 2, Kirby's Dream Land 3, and Kirby 64: The Crystal Shards. The twist is that the trilogy here would be the latter three games, thanks to all of them having several elements in common and an overarching story arc (mostly surrounding Eldritch Abomination Dark Matter, who Fanon named the trilogy after). Thus, the first game ends up being more of a setup for this entire trilogy (and also Kirby's Adventure, which is narratively unrelated) instead of part of it.
After the release of Leisure Suit Larry 3: Passionate Patti in Pursuit of the Pulsating Pectorals, series creator Al Lowe insisted that there wouldn't be a Larry 4, partly thanks to how Lowe essentially wrote himself into a corner without any idea how Larry 3's ending could lead into a sequel. Instead, he chose to skip the fourth installment (retroactively referred to as Leisure Suit Larry 4: The Missing Floppies) completely and carry on straight into Leisure Suit Larry 5: Passionate Patti Does a Little Undercover Work, where the absence of a fourth game is actually a plot point, and both Larry has amnesia because the Big Bad stole the Larry 4 disks, and weaseled out of paying Patti for her work on the score.
Mega Man:
- The Mega Man Battle Network series was originally going to end with the third game, but ended up going on for six games (not counting the Network Transmission and Battle Chip Challenge spin-off games).
- The Mega Man Zero series and plot threads were supposed to end with the third episode. However, the fate of one specific villain was left unresolved; this spiraled into Mega Man Zero 4 and the true Grand Finale for the series.
Hideo Kojima did not intend to direct any of the Metal Gear sequels beyond Metal Gear Solid. When he was brought back to direct Metal Gear Solid 2, he ended the story with an inconclusive ending and then followed it up with Metal Gear Solid 3, a prequel that was marketed as "the final game in the Metal Gear Solid trilogy." However, due to much demand after the open-ended nature of Sons of Liberty, Kojima was brought back again for Metal Gear Solid 4 to tie up all the loose ends and conclude Solid Snake's storyline. Despite this, the Metal Gear series continues on with a series of prequels starring Big Boss (such as Metal Gear Solid: Portable Ops and Metal Gear Solid: Peace Walker) and Metal Gear Rising: Revengeance (a spin-off starring Raiden). Then Kojima started directing Metal Gear Solid V: The Phantom Pain, which he claimed to be the final Metal Gear game he'd directly work on. Kojima has went on record saying that every time he announces a game as the franchise's last, he receives a bunch of death threats from rabid fans, and it's these threats that makes him rethink ending the franchise. The PR collapse of Konami appears to have given Kojima the go-ahead from fans to pursue non-Metal Gear ideas.
Metroid:
- Despite being called the Metroid Prime Trilogy, the Prime series already had a total of 5 games: adding a Spin-Off multiplayer-focused game called Metroid Prime: Hunters that was released between Metroid Prime 2: Echoes and Metroid Prime 3: Corruption that was entirely disconnected from the Phazon plot at the center of the first three numbered installments; and a a digital pinball version of the first Prime game. Then nearly ten years after Corruption, Nintendo released another multiplayer spin-off in the form of Metroid Prime: Federation Force, though this one did concern the overarching plot and tackled the aftermath of the original trilogy's events. Then, came 2017, and the announcement of Metroid Prime 4: Beyond, the 4th numbered entry in the series, which also further elaborates on story elements from "Hunters" and "Federation Force".
- Series co-creator Yoshio Sakamoto originally intended the original Metroid, Metroid II: Return of Samus and Super Metroid to be a trilogy, with Super being the conclusion of a clear narrative structure (Samus defeats Mother Brain and the Space Pirates, Metroids start becoming a galactic threat so Samus terminates all but one, Space Pirates and a revived Mother Brain steal the last Metroid for their plans and get defeated for good). Cue Metroid Fusion happened, which featured almost none of the previous plot threads, instead having Samus face off against a new threat that justified the existence of the aforementioned Metroids. This was followed by Metroid Dread, which had Samus manage to defeat said threat for good while also developing the powers of a Metroid herself, with Sakamoto labeling these five games as a pentalogy revolving around Samus and her relationship with the Metroids.
The Onimusha series was originally conceived as a trilogy, with Onimusha 3: Demon Siege initially advertised as the final installment of the series. It didn't take long for Capcom to produce a fourth game afterward, with Onimusha: Dawn of Dreams (aka Shin Onimusha).
After Prince of Persia: The Two Thrones wrapped up the trilogy started with Sands of Time and continued with Warrior Within, a handled spin-off titled Battles of Prince of Persia came out in the same month then a fourth game in the same continuity, titled Prince of Persia: The Forgotten Sands, was made in order to capitalize on the release of the Sands of Time movie. A Continuity Reboot had been produced in the intervening years.
When Ratchet & Clank jumped to the PlayStation 3, developer Insomniac Games began developing a storyline dubbed "Ratchet & Clank Future" that would expand on the backstory of the duo as well as their lineages as a whole, eventually taking the form of 2007's Future: Tools of Destruction and 2009's Future: A Crack in Time (the latter of which was also intended as the Grand Finale for the series as a whole). Once it became clear that A Crack in Time needed an additional year of development, Insomniac released Ratchet & Clank Future: Quest for Booty, a short Mission-Pack Sequel to Tools that served to both tide fans over and set up A Crack in Time. This also led the studio to start referring to these games as the "Future trilogy". Once PlayStation decided to keep the franchise going, a six-issue comic miniseries released which acted as an epilogue that bridged the ending of A Crack in Time into the then-upcoming entry All 4 One (which was not a part of the Future storyline). However after the less-than-stellar reception of that title and its follow-up Full Frontal Assault, Insomniac decided to go back to the Future games' storyline with 2013's Ratchet & Clank: Into the Nexus, which was explicitly advertised as an epilogue despite not carrying the "Future" label. Then, after eight years, that game would receive a direct follow-up with 2021's Ratchet & Clank: Rift Apart, which once again continued the storyline and further expanded on the backstory introduced in the PS3 titles. This means that the Future trilogy (which, may we remind you, started as two games) is now comprised of five games and a comic, and even then it's currently unknown if Rift Apart is the true conclusion as its ending leaves open the possibility of another direct continuation. Insomniac themselves seemed to be aware of this trope and attempted to downplay it, as once Into the Nexus rolled around they stopped calling it the Future trilogy and instead began referring to it as the Future saga.
In Sonic the Hedgehog, Shadow's story arc originally fit neatly into a trilogy: Sonic Adventure 2 depicts his origin and Heel–Face Turn; Sonic Heroes has an amnesiac Shadow dealing with the aftermath of the previous game; and Shadow the Hedgehog features his Archnemesis Dad, Black Doom, and ends with Shadow finally sure of who he is and vowing to put the past behind him, furthered by his next appearance in Sonic the Hedgehog (2006) having almost no allusions to any previous events. Almost 20 years after Shadow's self-titled game, Shadow Generations would continue the threads of these plotlines, with Shadow facing a revived Black Doom and finally getting closure with Maria and Gerald.
The Erebonia Arc of Falcom's Trails Series of games serves as a variation of this trope. It was supposed to only have two installments, but the first one ended up getting split into two games, allegedly due to hardware limitations. It would later get three more games due the creators wanting to tie up more loss ends. It wouldn't be until the next game that the story arc for the next country (Calvard) would begin.

Web Animation

The Animator vs. Animation series was originally supposed to end with Animator vs. Animation III, which ended with the Animator's computer being destroyed, taking the stick figures down with it. Two years later, the fourth installment was announced, and a year after that, Animator vs. Animation IV was released, and since then the series remains alive with new installments coming out.
Fallen Kingdom (CaptainSparklez): Or rather, Tetralogy Creep. "Dragonhearted" was released in November 2016, and everyone thought it was the end of the story... until "Rising Kingdom", a prequel, was released in December 2022. Lampshaded in the latter video's description:
After 6 years, we revisit the not yet Fallen Kingdom.
The Lazer Collection was originally only going to be three parts long, but when requests for a fourth part were continuously made, the author eventually made it, but it's a case of Stylistic Suck with a subtext of "Now Shut Up." There's also a Part Five.

Web Original

Lindsay Ellis:
- Parodied by The Nostalgia Chick: Her three-part review of The Lord of the Rings ended with her talking about how a lot of the material got pushed into the Extended Edition... and then ends by announcing that the reviews will have an "Extended Cut," i.e., a fourth episode.
- Ellis did it again with her two-part review of The Hobbit suddenly getting a third part, parodying how the films were expanded from a planned duology to an overly long trilogy.
The Super Best Friends Zaibatsu coined the term "Sadness Trilogy" for the David Cage games Indigo Prophecy, Heavy Rain, and Beyond: Two Souls when the latter came out. A few years later, they played Omikron: The Nomad Soul, which became "Episode Zero" of the Trilogy. Then Detroit: Become Human came out, and the term was largely phased out by them (also as recognition of the fact that Detroit was a game they actually enjoyed and there wasn't much to be sad about in its case).

Western Animation

Parodied and exaggerated in the first act of the Lilo & Stitch: The Series episode "Skip". Lilo and Stitch want to go watch Wasp Mummies III. After they skip ten years in the future so Lilo would be old enough to watch the film, they find that the Kokaua Town Cinema (or now Cinemas) is now showing the ninth Wasp Mummies film, Wasp Mummies IX: Return of Another Final Chapter – Part 2.