Assimilation Plot

""I will bring peace to the world. Everlasting peace. And unity. And uniformity.""

- The Cyber-Controller, Doctor Who, "The Age of Steel"

This trope refers to a common plot by the villains with a cause, wherein they reason that all of humanity's problems and unhappiness are caused by people being separate/different from one another, and so try to forcefully eliminate the differences and individuality of everyone by merging everyone into one mind/body/soul/etc.

Basically, this is when villains use supernatural/AppliedPhlebotinum means to make a Hive Mind because Utopia Justifies the Means, and is often done by a Well-Intentioned Extremist/Totalitarian Utilitarian/Knight Templar. This is how The Virus justifies itself, if sentient and possessing a Hive Mind.

Variants include:


 * 1. Less noble minded villains who seek to create a Hive Mind just to make themselves the Hive Queen. In this case, the villain has a Take Over the World goal but with a twist. They may use the Well-Intentioned Extremist cause as a ruse.
 * 2. Curious villains who want to see if it can be done and what would happen. This kind of guy is likely to hear You're Insane! often and not care.
 * 3. Other. The character involved may have some other reason. For instance, Gendo Ikari from Evangelion wanted to  which was completely different from SEELE's goal.

Compare/contrast The Evils of Free Will, where the villains use force, brainwashing, and other things to systematically eliminate unique thinkers until everyone is basically a carbon copy, but remains an individual physically. A standard feature of pretty much every Dystopia, ever.

See The Singularity for a "natural" version where exponential technological change causes assimilation. See also Pieces of God, where humanity actually started as one entity. See Mental Fusion for a smaller scale, voluntary assimilation.

Not to be confused with The Assimilator, which is a character trait rather than the focus of the entire plot. There the character is simply expanding instead of something visionary, though a visitonary Assimilator might devise an Assimilation Plot.

A step up is the World of Silence, where everyone is not only one but that 'oneness' is one of complete apathy and nothing.

Anime and Manga
"Brera: Being connected to you scoundrels, I truly realized: no matter how far we go, humans are always alone. Brera: But-! Alto: It's because we are alone... that we can love someone!"
 * Neon Genesis Evangelion: Its version of this was the former Trope Namer, but renamed possibly because it spoils too much.
 * Season 4 of Yu-Gi-Oh! GX:
 * Can't forget Season 3 where
 * This is the goal of in Code Geass. It's essentially the same basic idea behind the Eva version, but with a different set of symbols, and no Tang involved.
 * Interestingly, the assimilation plot is not even the final threat in the series.
 * The anime series Kaiba has a giant plant monster that consumes memories and planets that contain them. When the threat comes towards a planet the main characters are on, Popo,, wants the world to be eaten to unify all people and their memories.   seems to agree with this idea.
 * In Macross Frontier, Big Bad 's Evilutionary Biologist plan is to use her cybernetic implant based brain network and the FTL-communications of the Vajra's fold quartz to link everyone in the entire galaxy into a single group mind. Unlike the trope, however, the heroes discover that the network will have an "admin" position which will effectively put one person's desires over everyone else hooked into it,  The final episode even has what may be a Shout-Out to Evangelion in this memorable exchange:
 * In Macross Frontier, Big Bad 's Evilutionary Biologist plan is to use her cybernetic implant based brain network and the FTL-communications of the Vajra's fold quartz to link everyone in the entire galaxy into a single group mind. Unlike the trope, however, the heroes discover that the network will have an "admin" position which will effectively put one person's desires over everyone else hooked into it,  The final episode even has what may be a Shout-Out to Evangelion in this memorable exchange:
 * That's why we-!


 * Noein:
 * The British Library's ultimate plan in ROD the TV is to broadcast the mind of Gentleman across the Earth, rewriting the minds of every single person.
 * Before the final battle, Anita returns to Japan to discover that the British Library erased all memory of her from her former classmates' minds, going so far as to turn her admirer Hasami straight. Wendy confronts her, telling her to "live the dream or die." When Hisami manages to remember, Anita's happy - until full realization of the Library's horrific power strikes her.
 * It's revealed in Tengen Toppa Gurren Lagann that this is what the Anti-Spirals did to themselves,  The only individual among them is the Creepy Monotone god-like leader.
 * It's heavily implied that said god-like leader is not an individual at all - rather the collective will of the entire race.
 * Xam'd: Lost Memories.
 * Appleseed EX Machina:
 * This is a side effect of the MacGuffin in Paprika, where more and more people share the same dream. While the Talkative Loons with no self-preservation instincts start parading around Tokyo are bad enough, It Gets Worse when
 * Naruto:.
 * A relatively mild version of such a system is the central focus of Komi Naoshi's oneshot manga, Personant.
 * The Military leaders in Fullmetal Alchemist seem to think along these lines. It even sounds like EVA (SEELE, anyone?):

"Computer: Having achieved what they believe to be the ultimate form, they've decided to pursue galaxy-wide perfection, through a process that involves using light to transform other beings into their uniform image, referred to as "assimilation". Sound familiar? *cough*Borg*cough"
 * This seems to be the goal of the weakness-hating, Kira-esque genius Villain Protagonist of Lost+ Brain, who has.
 * Zonder metal in King of Braves GaoGaiGar was initially developed as a method of stress relief and a means to remove negative emotions, but it quickly went haywire and turned people into seemingly emotionless beings bent on assimilating the whole universe in a quest to remove negative emotions, which is explained to have been extended to such emotions such as joy, courage and compassion. Not surprisingly, the Zonders, Zonderians and the closely related Primevals are the main villains of the show.
 * Appears in Eureka Seven, though mostly in the backstory. Absorbing other beings into itself is described as the Scub Coral's only method of communication, and towards the end of the series, the idea of  is brought up; Thankfully, Renton & Eureka's efforts managed to avert this from happening.
 * This is the ELS's main tactic in Gundam 00 a Wakening of The Trailblazer. If enough ELS gather together, they can assimilate space cruisers (or even, it's implied, entire planets).
 * In the Axis Powers Hetalia movie, Paint It White, this is the goal of the Pict.


 * This appears to be the eventual goal of  in Gun X Sword.

Comic Books

 * In the Grant Morrison comic series The Invisibles, both the heroes and the villains want to bring about an assimilation. Their methods and perceived condition in the assimilation, however, differ.
 * Another Grant Morrison series, The Filth, has a villain/collective with a more grossly physical assimilation in mind.
 * Deadpool
 * A Well-Intentioned Extremist in a Cable & Deadpool story arc just wanted to end racial strife by making everyone the same color - blue. He successfully pulls it off (though everyone winds up pink due to Cable's meddling). Deadpool convinces the antagonist that his plan was flawed from the start by taking him to an airport and simply identifying the race of passers-by.
 * In kid-superhero comic PS238, Badass Normal-in-training Tyler Marlocke got to take a peek at a variety of alternate universes where he was born with powers. In one of them, he was a psychic so powerful that he accidentally caused one of these by touching every human mind at once -- and then was ejected from the collective, leaving him the only individual mind on Earth.
 * In something of a departure from norm, said Hive Mind (The Commonality) is presented as a benign entity that's turned Earth into a Utopia and holds that universe's Tyler in very high regard for having created it. It's not much consolation for Tyler, though, as he is terribly lonely without any non-assimilated humans to talk to.
 * A What If comic explored the consequences of the High Evolutionary kicking all of the humans, superhumans, and mutants in the Marvel Universe into their most highly evolved state and uniting into a single being; instead of achieving The Singularity or Ascend to a Higher Plane of Existence as the H.E. had hoped, it/they essentially destroyed the universe and left the High Evolutionary stranded forever on a timelocked Earth stuck outside of reality. Oops.
 * Played with in Dark Empire. Palpatine wants to create an assimilation... which only exists to feed his (and perhaps Darth Luke's) immortality. Literally the entire Skywalker-Solo family ultimately kills him, and even the dead Sith don't want to be around him in the afterlife.
 * During Marvel's War of Kings crossover,
 * A Dream Vortex can do this without even being aware of it in The Sandman. At some point, they will start breaking down the walls that divide peoples' dreams, the problem being that this eventually kills everyone on the planet unless Morpheus steps in to Shoot the Dog. This is the only circumstance in which the rules governing his actions allow him to kill someone in cold blood.
 * A Dream Vortex can do this without even being aware of it in The Sandman. At some point, they will start breaking down the walls that divide peoples' dreams, the problem being that this eventually kills everyone on the planet unless Morpheus steps in to Shoot the Dog. This is the only circumstance in which the rules governing his actions allow him to kill someone in cold blood.

Eastern Animation

 * In Time Masters, Gamma 10 is inhabited by faceless male angels who worship one amorphous, all-controlling being. Hmm. They capture the heroes and plan to change him into one of them to power their God, which would make lose all sense of their individuality as the faceless angels did -- they were once scruffy spacemen.

Literature

 * Childhood's End: The plot involves . It's also mentioned that the Overlords lack the capacity for this.
 * A Wrinkle in Time: The planet Camazotz is governed by . All activities are completely synchronized. When the Big Bad brags to the heroes that Camazotz has achieved complete equality, the heroine delivers an insightful response, and one that in retrospect should have been obvious: "Equal and alike are not the same thing!"
 * In Ursula K. Le Guin's The Lathe of Heaven, one of Dr. Haber's many disastrous attempts to productively use George Orr's reality-warping abilities leaves everyone on Earth with an identical grayish skin-tone to end racism; nice as it sounds, this colorblindness makes people who are "too black" simply cease to exist.
 * In the short story/novel Blood Music by Greg Bear, assimilation is caused by
 * The Giver skirts the border between the natural and supernatural versions. "Sameness" is enforced by rigidly controlling every stage of life, depersonalizing the family unit, "releasing" those who don't fit in, and breeding out the ability to see color, but it's also somehow dependent on one person holding back all the memories of the past, which can be transferred through some kind of psychic ritual.
 * A psychic ritual which can only be done between people with blue eyes. And the colorblindness thing is at least not entirely physical, either; being able to see color is connected to the ability to transfer memories, and seems to be stronger as one accumulates a bigger memory stockpile. And vice versa, since the titular character becomes colorblind after transferring the majority of his accumulated memories to the protagonist.
 * Actually, it doesn't need to be color first - the previous Giver
 * This is the goal of the The Virus (literal, in this case) in the Repairman Jack novel Hosts, though
 * Isaac Asimov's fourth book of the Foundation series, Foundation's Edge, which contains an already-assimilated world called Gaia, has the main character.
 * Although it's not for any of the usual reasons.
 * Also the short story, "The Last Question" actually depicts humanity as a single united entity at the end.
 * The second and third Boogiepop novels (VS Imaginator Parts 1 and 2) feature a villain calling herself the Imaginator who's half-possessing/half-controlling someone with a psychic ability that may progress towards assimilation as an ultimate goal. However, Boogiepop points out
 * The real Big Bad in the Codex Alera by Jim Butcher are  bemoan concepts such as individuality and self-expression and seek to unite all life in one massive ball of green goo.
 * The Arbai Trilogy by Sheri S. Tepper brings us the Hobbs Land Gods, which unite those under their influence into a collective hive-mind.  In the third novel, Sideshow, the planet Elsewhere has planetary-government mandated diversity as a countermeasure to this.
 * Doesn't actually happen in "The Culture" novels, but is part of the reason why the Culture is suspicious of entire civilizations subliming all at once. It implies coercion.

Tabletop Games

 * In the White Wolf RPG Mage: The Ascension's "canon" ending,.
 * In the White Wolf RPG Vampire: The Masquerade's Crucible of God ending,
 * In Dungeons and Dragons, the culture of the illithids is built around this trope, as each individual anticipates becoming united with its fellows at the end of its life, when its brain is grafted into the huge disembodied elder brain which leads their community.
 * In Magic: The Gathering many white mana Phyrexians believe in the "Flesh Singularity", which is this, except without people having separate bodies. They think paradise will be achieved when everyone in the world has been grafted, sutured or riveted into one enormous organism.
 * In Runequest the Empire of Wyrmfriends believes that everybody, be it mortal or god, has a secret draconic nature that everybody should embrace. And they mean EVERYBODY. Also, the Lunar Goddess wants everybody to be illuminated and worship her.

Television
"Cyberman: But you need not fear. Cybermen will remove fear. Cybermen will remove sex, and class, and color, and creed. You will become identical. You will become like us."
 * Cybermen in Doctor Who.


 * In "The End Of Time",

"Locutus: Why do you resist? We only wish to raise quality of life for all species. Worf: I like my species the way it is. Locutus: A narrow vision. You will become one with the Borg. You will... all... become one with the Borg."
 * While primarily selfish scavengers of biology and technology, the Borg show hints of this in Star Trek the Next Generation:


 * Then there's a strong argument that The Federation is one in action, with a plan to join all in one Utopian government. This is a problem for the Maquis, who choose to leave the Federation. In Deep Space Nine, one of their leaders actually compares the Federation to the Borg, who at least let people know they're going to be assimilated.
 * The difference is that the Federation doesn't force people to join.
 * Apparently, the problem with the Maquis was not that they wanted to leave, it was that they were willing to declare war on both their former countrymen and the invaders who wanted their home. Since they were willing to fight, the Federation felt forced to defuse the situation with combat. That many of the Starfleet officers who chose to join the Maquis did so by committing espionage and acts of explicit treason (such as stealing weapons and equipment from Starfleet or providing classified information on fleet movements and patrols), contributed to the Federation's view of the Maquis as rebels and traitors and not as seceded members of another political sphere.
 * Jasmine in Angel, although her followers were still individuals to a certain extent.
 * An evil version of this trope was one of the plans of the First Evil in Buffy the Vampire Slayer: to possess mankind en masse once.
 * The titular creatures in the Star Trek the Original Series episode "Lights of Zetar" are a floating energy hivemind comprised of the last members of a doomed civilization. Their goal is to find a compatible human to merge with so they can regain physical sensations and abilities.

Video Games
"The Many: Mistrust is the tyranny of the individual. Your own kind sees you as a threat. The Many: We do not know death... only change. We cannot kill each other without killing ourselves. Is your vision... so small... that you cannot see the value of our way? The Many: The Machine Mother... told us of the planet of her birth. We know how you have harmed this place... with your pollution, your violence, and your discord. But when we arrive there, we will cleanse the surface of that place, and merge it... with the harmony... of the Many."
 * A good number of Space Empire games or Civilization-style games with technology that goes well into the future, (including Sid Meier's Alpha Centauri,) will feature some blend of this and Ascend to a Higher Plane of Existence as their ultimate technology, and the means of achieving the Technological Victory. It's worth pointing out that this is portrayed as Ascend to a Higher Plane of Existence, and almost always shown as heroic and that nobody at all minds the thought of leaving their bodies behind, the way that the ragtag band of heroes always will if it wasn't their idea first. Alpha Centauri is notable because it expressly involves melding with Planet, which has been sending out creatures to inflict a Fate Worse Than Death for the entire game until then. The faction that pulls this off "wins" by having its values become predominant in the new consciousness.
 * In Alpha Centauri it's played as a side effect of the attempt to survive Planet awakening and effectively becoming god. All the story pop-ups make it very clear that the path leading up to that ending is a desperate attempt to survive.
 * The World Ends With You:.
 * To right the countless wrongs of our day, we shine this light of true redemption, that this place may become as paradise. What a wonderful world such would be...
 * Tales of Symphonia:.
 * Subverted when
 * That's more "The Evils of Free Will" than an Assimilation Plot, since those affected all retain their physical forms.
 * Assassin's Creed: The Knights Templar want to launch satellites into the Earth's skies containing alien technology plundered from  to use their religious brainwashing power to cause everyone to think exactly alike..
 * Final Fantasy X:.
 * Sometime between Mega Man Zero and Mega Man ZX, somebody got the big idea that the only way to end the fighting between Humans and Reploids was to make them the same. Aside from the occasional Mavericks or the games' Big Bads, it works. The only real difference between a Human and a Reploid now is the means of their birth/creation.
 * As well as those nice little red triangles on the heads of Reploids to differentiate between the two.
 * This would be a very mild example. Everyone still has their individuality, it's just that Reploids no longer have robot super powers built in.
 * Or, rather, that humans have super powers built in on par with those of reploids (case in point: when Ashe-- a human-- * jumps off an airship at cruising altitude* casually and without even the remotest hint that she thinks the maneuver is at all dangerous). Though it seems to be true that the average reploid isn't as powerful as, say, X or Zero, that was true during the X and Zero series as well (which is why X and Zero were the player characters).
 * Specifically, humans were getting augmented with robotic parts, to enhance heir capabilities, and Reploids started getting programmed with lifespans, which could not be exceeded, so they would die too, with the end result being no practical difference between the two.
 * System Shock 2:

"Harbinger: That which you know as are your salvation through destruction."
 * In Xenogears, Krelian wants to bring about an assimilation to salve his heart of the pain of losing Sophia. He does this by literally getting most of the world's population to mutate and become part of the flesh of a giant, organic weapon called Deus.
 * Darkstalkers: Demon prince Jedah creates a giant creepy baby fetus and attempts to unite all of the world's demons and monster souls within it to become one being. The world's demon and monster population have quite a bit to say about that. Sad part is, considering the downward spiral said demon population's got going for it, assimilation might be necessary.
 * The Unitologist Church in Dead Space seems to have this as its central dogma: Humanity was created by Sufficiently Advanced Aliens (Or maybe God? Unclear), and life as we know it is a stepping stone towards "Convergence", when "all will be made as one"... or something. Point is, quite a few of them seem to think the Necromorph transformation is what leads to Convergence (since Necromorphs seem to be united under a Hive Mind), and quite eagerly embrace it for themselves and their fellow man.
 * Even though EarthGov and the Church are publicly opposed to eachother, they seem to believe the same things.
 * Although it might not totally fit the trope, the Khala in Starcraft is a heroic example. Since by the time just before its discovery, the Protoss are fighting a massive civil war, and the discovery of Khala by Khas/ ended the civil war and helped restore psionic link that was lost in the war. Though to be noted that even they are linked the protoss still retain individuality.
 * A smaller example of this would be the creation of the Archon, which requires two Templars to sacrifice their individuality to create one incredibly powerful being of energy.
 * Starcraft is indeed interesting as exampled in volume 3 of Frontline manga. It seems like some protoss do consider the Khala as hive-mind (even though they retain individuality and it's like a free-over-the-galaxy-telephone-for-zero-cost) and even for that little the exiled dark tamplars reject it (and happy with just normal telepathy). As for archons it seems like a case-by-case, the in-game unit has no personality and only urge to destory its enemies, the Twilight Archon is a something unique altogether (and we don't know what its personality like) and Ulrezaj is made of 7 dark templars but only Ulrezaj original personality controls the body.
 * Also the Zerg are hive-mind... sort of. In the buttom line the Overmind and the cerebrates have distinct personalities but "hard-wired" in a way that they cannot rebel thus lacking some of the free-will. Also basically anything beneath them (every other zerg unit) is just a creature with no personality or free-will whatsoever. Kerrigen and some doubtfully-canon zerg are different.
 * One of the endings in Shin Megami Tensei III: Nocturne is the creation of the Reason of Shijima, essentially an assimilation. It is initiated by having the Demi-Fiend join forces with the man who caused the Conception and created the Vortex World.
 * The game also contains the opposite. One of the Reasons involves creating a world of ultimate individuality, where each person has only themselves to rely on, and nobody can interfere with the life of anyone else.
 * Arguably, the game begins with one: most humans instantly die during the Conception, only to be reduced to Tang... err, Magatsuhi.
 * In Shin Megami Tensei: Strange Journey, a variant of this is the goal of the Law faction. Specifically, they want to brainwash the entire world into doing nothing but praising God and the angels, with only a few people they deem worthy retaining any vestige of individuality.
 * The fourth game in the Heroes of Might and Magic series has a Big Bad (in the Order campaign, naturally) with something similar as his goal--he wants to eliminate free will, and so end war.
 * At the end of Deus Ex Invisible War, if you side with Helios, the whole world is united in a Hive Mind under the supervision of the AI Helios.
 * This is the ultimate goal of, of Ar tonelico 2, to create a world where all people can exist in peace and happiness for eternity by launching them into their own separate virtual realities under the global network, where they may live as gods through SUBLIMATION. Considering that the towers that support the little remaining human life in an otherwise completely dead world that they believe is sentient, and deliberately trying to kill all humanity, are crumbling and failing, and they already tried, and failed, to use the only other option, METAFALICA, unlike most other practitioners, it lands them squarely in Anti-Villain territory for trying this one. The heroes still stop them and try (and nearly fail) METAFALICA, anyway.
 * Something similar was tried earlier in the game with Hibernation (or Haibanation in the original version). The difference is that, while Hibernation would involve everyone in Metafalss, Sublimation was the worldwide version.
 * In Pokémon Diamond and Pearl/Platinum, this is the ultimate goal of Team Galactic's leader. He traces spirit; emotion, willpower knowledge, etc. as the source of all the world's imperfections. So he plans to use Dialga and Palkia; masters of Time and Space, to unmake the current world and build a new world, one without spirit. And even after you beat him, he hasn't given up...
 * Conversations with Legion in Mass Effect 2 indicate that this is the ultimate goal for both the Geth and.
 * The Geth are a machine race where sapience is achieved by the cooperation and consensus of a multitude of lesser non-sapient programs and sub-routines. Their ultimate goal is . Unique in that no member of their race opposes this goal - an 'individual' geth is a piece of software, so they need to be networked to achieve sapience.
 * On a grimmer note are

"Gravemind: Do not be afraid... I am peace, I am salvation."
 * Does this all remind you of something?
 * Bioshock 2.
 * In Halo 3, Gravemind has a few quotes suggesting that's what the Flood view as their ultimate goal.

"The Master: The Unity will bring above the master race. Master. Master! One able to survive, or even thrive, in the wasteland. As long as there will be differences, we will tear ourselves apart fighting each other. We need one race! Race! Race! One goal! Goal! Goal! One people... to move forward to our destiny. Destiny."
 * In Fallout, the Master seeks to create the "Unity": a single race of super mutants, via (mostly) forced assimilation.


 * The ultimate plan of The Burning Legion is to destroy all traces of order in existance while recruiting races they come across to their ranks by corrupting and them and turning them into demons as well.
 * The Grigori in Star Ocean: The Last Hope seek to achieve instrumentality of the entire universe by eradicating all life, and replacing them with souless copies that act under their will.

Web Comics

 * The fifth chapter of Fans kicks into high gear when starts humanity on the path to assimilation by accident.

Western Animation

 * Megatron's goal in Transformers: Beast Machines is to absorb every other spark on Cybertron and thus creat a brand new world with himself as its single guiding intelligence. Fanon sometimes claims this as a ridiculously long-term Gambit Roulette by Primus.
 * In Fairly Oddparents, Timmy wishes everyone was the same after dealing with some arrogant jerks, turning everyone into gray blobs. However, they remain arrogant jerks (declaring themselves to be the "grayest and the blobbiest" of gray blobs), and he realizes that changing what people look on the outside isn't going to change what they're like on the inside.
 * In the Crossover between The Grim Adventures of Billy and Mandy and Codename: Kids Next Door, Billy, Grim's scythe, the Lucky Pants and the Delightful Children from Down the Lane are accidentally fused together to create an entity known as the Delightful Reaper, which then proceeds to absorb every person it comes accross until it grows to Kaiju-sized proportions. Mandy then allows herself to be absorbed by the Reaper so she can perform a Split Personality Takeover on it.

Real Life

 * There are several concepts of Death being a form of assimilation, since existence generates matter and therefore, identity. One might be the Christian concept of Heaven, "all will be united with God".
 * Modern interpretations of the Afterlife, like "Universal Reconciliation" (all souls will be reconciled with God) and "Eternal Separation" (good people unite with God, bad people are left to fend for themselves in an existential vacuum) presents Heaven / God more in this manner, to replace the Orwellian Word of Dante (Hell) that dominated Christian thinking for so long.
 * The concept of Nirvana in Buddhism is considered a form of this by some sects; an existence without suffering or desire as the highest happiness. However, in at least some subsets of Buddhism, individual personalities still exist in this state.
 * Many New Age-types who believe that the re-setting of the Mayan calendar, to take place on Dec 22nd, 2012, will result in an assimilation.
 * Apparently, Pete Townshend wanted to manage this with Lifehouse. That's right, kiddies - the lead guitarist of The Who wanted you to die of joy at the end of "Won't Get Fooled Again". Luckily for us, the attempt to realize this drove him nuts before he could pull it off.
 * He came close.
 * Russian composer Alexander Scriabin spent the last 12 years of his life working on a musical work called Mysterium. He planned only one performance of his work, at the foothills of the Himalayas. It would last seven days, and would lead to the end of the world and the replacement of humanity with purer forms.
 * There was also Carl Jung's concept of a "Collective Unconscious", which is pretty much the Freudian Unconscious on a cosmic, universal, impersonal scale that connects all individuals and resembles more of an Akashic Record. It's kinda a Mind Screw to fully explain (although the concept was featured in Serial Experiments Lain).
 * This happened a lot in colonised nationed, usually out of misguided charitable notions.
 * This is one of the arguments in favour of school uniforms; to make all students equal. It's also the main argument against them.

Anime and Manga

 * Serial Experiments Lain. This time, it featured both the Collective Unconscious (see Real Life folder above) and The Internet a.k.a The Wired (see Real Life folder below)
 * Major theme of Ghost in the Shell: Stand Alone Complex, series 1 and 2, as a natural result of an interconnected cybernetic information network. Natural assimilation underlies the concept of the "Stand Alone Complex" itself, and it is explicitly examined in the case of.

Comic Books

 * The stated goal of the Chitauri in The Ultimates. Of course, since they apparently get their ass kicked not only on Earth, but all up and down the Galaxy, before getting anywhere close to wiping out the "cancer" of individuality, it's not clear if this goal can even be achieved.

Film

 * This is the ultimate goal of the alien parasites in the movie The Invasion.
 * Not as stressed, but also an ultimate outcome of the earlier Invasion of the Body Snatchers movies.
 * The country of Libria in Equilibrium. On top of outlawing emotion and destroying anything (art, books) that could cause an emotional reaction, the government boasts that it has brought harmony to the people by also enforcing conformity and sameness. Everybody dresses alike, lives in identical housing, and has virtually the same daily routine.
 * Fight Club uses this later on to build the "space monkey" army for Project Mayhem.
 * This is the ultimate goal of the alien queen in The Faculty.
 * The goal of One Nation Earth citizens during the Tribulation to unite together for world peace, interpreted as the people becoming one in mind like those who attempted to build the Tower of Babel, heavily emphasized in the Apocalypse film series movie Tribulation as police officers and One Nation Earth agents hunt down those who have not taken the Mark of the Beast and force them to enter the Day Of Wonders program.
 * Loki in The Avengers invokes this to take control of people. He full on believes that humans are weak and corruptible with free will and that we need someone to rule us and decide for us to be peaceful.

Literature
"Jorj X. McKie: We survive by selecting the best decision makers. And a DemoPol elevates mediocrity. (The Dosadi Papers, BuSab reference): 'Behavioral engineering in all of its manifestations always degenerates into merciless manipulation. It reduces all (manipulators and manipulated alike) to a deadly "mass effect." The central assumption, that manipulation of individual personalities can achieve uniform behavioral responses, has been exposed as a lie by many species'. 'Given any species which reproduces by genetic mingling such that every individual is a unique specimen, all attempts to impose a decision matrix based on assumed uniform behavior will prove lethal.'"
 * Brave New World: The World State successfully established a For Happiness hivelike utopia where everyone is kept content and docile through sex, drugs, a highly efficient caste system, mass-production and Pavlovian brainwashing techniques, at the cost of individualistic thinking.
 * Also, the lower groups are bred in large groups from the same ovum.
 * In This Perfect Day by Ira Levin, genetic engineering, selective breeding, involuntary medication have been all used to slowly breed the human race into near-identical, interchangeable people, who are all selfless, non-violent, and helpful to a fault. They even look pretty much the same, with similar light-brown skin, vaguely slanted brown eyes, and not a whole lot of difference even between the sexes. Of course, the hero rebels against this conformity, and ultimately overthrows the supercomputer that controls everything and enforces this conformity.
 * Harrison Bergeron, a dystopian science fiction short story written by Kurt Vonnegut, Jr. Societal equality has been achieved by handicapping the most intelligent, athletic or beautiful members of society down to the level of the highest common endowment. This process is central to the society, designed so that no one will feel inferior to anyone else. This is overseen by the United States Handicapper General, Diana Moon Glampers. For example, a person stronger than most people is required to carry many pounds of lead bird shot in a sack around their neck so as to offset their "unfair" strength. Highly intelligent people have soundchips implanted in their brains to play distracting noises that prevent them from keeping an extended train of thought. Other means are used for other "unfair" advantages, like beauty.
 * A significant portion of the climax of the story appeared on Public Television in 1972 as part of the Vonnegut tribute/pastiche Between Time and Timbuktu.
 * He used a similar idea in The Sirens Of Titan -- while the handicapping is less extensive, everyone in the Church of God the Utterly Indifferent has to be at least symbolically handicapped, since the key tenet of the religion is that luck is not the work of God and should be eliminated.
 * The Uglies series of books has everyone going through extensive surgery after they turn 16 so that everyone is pretty. Naturally, there is more going on.
 * Something similar happens in the classic Twilight Zone episode "Number 12 Looks Just Like You." People's bodies are altered to make them prettier/handsomer, and their brains are altered to make them only care about superfluous things like fashion, etc.
 * Stanislaw Lem wrote a series of short stories called The Star Diaries about the misadventures of a Polish Unfazed Everyman Cosmonaut named Ijon Tichy. One story has Tichy visit a series of societies by "The Great Architect", whom Tichy is supposed to meet. The last society is one where everyone is engineered to look exactly the same, and there's a lottery where everyone takes a different role in life (banker, janitor, wife, child, etc.) every week. This is the Architect's "masterpiece", because it eliminates identity, and thus eliminates death. Tichy then decides the Architect is completely off his nut, and runs away as fast as possible.
 * The Hive Mind formed by the Green Patches in Isaac Asimov's short story Green Patches. As you can tell, this is something of a recurring theme in his works.
 * Deconstructed in Neal Stephenson's Cryptonomicon, in which Andrew Leob's backstory involves a failed attempt to unite all of humanity in a single Hive Mind which failed because, apart from wanting to unite all of humanity, none of Leob's followers could agree on anything.
 * Alan Dean Foster's novel Design for Great-Day features the Solarian Combine, a vision of the potential future of mankind as merely one member of a galaxy-spanning "supermind", capable of enormous mental feats and extremely close to having power over matter/energy itself. This is portrayed as a good thing, as Foster is very consistently on the ideal side of the Sliding Scale of Idealism Versus Cynicism.
 * The State in Jack L. Chalker's Well World series, in an Alternate History where the Soviet Union never fell, and Communism became the default human government, tries to make this a reality on many of its more "advanced" planets, engineering humans in Birth Factories to be physically flawless but mentally ant-like workers and on some worlds even hermaphrodites, so everyone's equal.
 * Effect of DemoPol used by Humans in Con Sentiency history resembled this, and some still are a bit upset when it's considered:

"Inner Party member to Winston: Alone-free-the human being is always defeated. It must be so, because every human being is doomed to die, which is the greatest of all failures. But if he can make complete, utter submission, if he can escape from his identity, if he can merge with the Party so that he IS the Party, then he is all-powerful and immortal."
 * Be A Perfect Person in Just Three Days extols the necessity of broccoli in pursuit of a very quiet assimilation with lots of vitamins.
 * The philosophy of Ingsoc from Nineteen Eighty-Four claims to be this. Party members, thanks to the Big Brother Is Watching system and heavy conditioning, are reduced from individuals to just on/off switches through doublethink, accepting both mutually contradictory ideas and agreeing with whatever the vast Party mind wants, even though it completely contradicts with facts and history. The Phlebotinum which the collective uses to bind together its components and fuel itself is simply endless mass war hysteria and pure power, specifically power over other human beings. Freedom is slavery, and if there is a slight deviation of thought within one of the Party members, they are subjected to institutionalized Mind Rape. Not to mention Ingsoc is also known as the "Obliteration of the Self."

Live Action TV

 * Betti's goal in Parallax is to "blandish" every universe - that is, make everyone in it the same, and thus eliminate disharmony. Note that she doesn't want every universe to fit a particular mould - every universe can have its own, provided everyone fits it.

Music

 * The They Might Be Giants song "The Bells Are Ringing", whose lyrics deal with mind controlling bells that organize people into a single mind. A girl tries to resist by putting cotton in her ears, but at the end, "As if by hidden signal/The people turn to face her/One thousand eyes are staring/They pull away her earplugs".

Video Games

 * This is the master plan of Helios from Deus Ex and its sequel, Invisible War, made possible through nanotechnology. Oddly enough, helping him do this is the closest thing Invisible War has to a good ending. This is possibly because he's upgrading everyone to eliminate inequality, rather than downgrading everyone.
 * According to J.C. Denton, Helios' goal was to give everyone nano-augmentations, so that everyone would have enhanced strength, intellect, be free of insanity, and so on, while retaining their sense of individuality, thus creating a true meritocracy (Helios would also be able to read everyone's minds and respond to their desires, which J.C. refers to as "instantaneous democracy"). Of course, the reliability of what Denton says is something that's left for the player to decide, and the ending where you help Helios win is kind of creepy.
 * Averted with the Omar, the game's more "obviously" "evil" cyber faction. Although they are a Hive Mind that occasionally recruits members through deception or force, they are actually SocialDarwinists instead of The Virus. Their goal isn't to assimilate the rest of humanity, but rather to let humanity die out, so they can step in and fill the vacuum.
 * The ODE System from Super Robot Wars attempts to do this. Its creator, Wilhelm von Juergen, fell into one massive Wangst after losing his family, thus thinking that if humanity unites into one to protect the Earth, nobody needs to be sad like him, thus he radically changed his normal system into this. Too bad the system ends up going Knight Templar.

Web Comic

 * In the Warren Ellis Webcomic Superidol, the whole world wants to be so much like a popular Idol Singer that they start acting, dressing, and even getting surgery to be like her, until everyone is a clone of her.

Real Life

 * The Internet. A global network which seduces large numbers of humans with the GIFTs of anonymity, free speech, global communication, and the promise of omniscience.
 * Many Singularitarians want this to happen. Which is something other Transhumanists use to ridicule them (not belief in The Singularity, the belief that we should merge into one superintelligence).
 * And then there are those who want to retain autonomy while still enjoying the advantages of a network.