The concept of clones or copies being made to replace original people, usually to teleport by creating a copy somewhere else and destroying the original or creating clones to replace a dying or dead original.
The Twin Maker is often a convenient way of bringing a dead character back from the dead without needing to invoke any trope that revives the old character. In manner and appearance, they are almost always perfect doppelgangers, indistinguishable from the original. This trope is often used in a science-fiction setting, where it can be readily justified by any amount of technobabble on cloning, teleportation devices, copying machines, and the like. Fantasy and other works involving magic are also natural habitats for this trope. When an original is not dead yet, there may be some interaction between them and their clone, but usually it's a case of Never the Selves Shall Meet.
Where this trope gets interesting is how the moral status of the new copy and the moral implications of disposing of the original are handled. First, the treatment of the twin: Some characters won't see the problem with treating them both as if they were the same person, whereas others will point out that it only works from an external viewpoint: the person will seem exactly the same to everyone else, but the actual stream of consciousness has been severed,note and the new copy is, in this sense, a completely different person. Sometimes it will be argued that the copy doesn't count as the original person, though given how interchangeable they would be if the paperwork for their birth certificates were ever mixed up, this argument is harder to hold up for long.
Second, the ethics of disposing of the original: If this matter is addressed at all in fiction, the Uniqueness Value and Cloning Blues tropes may well be invoked or played with as part of the story. A teleportation machine that worked in the manner of the short story To Be (see quotation above) would probably be regarded as a killing machine, but if there is any doubt about whether the stream-of-consciousness continues or not, the issue may well be sidestepped. If nothing in the device suggests anything sinister, it's generally treated as harmless.
Occasionally, the dilemma may even be taken a step farther, if the Twin Maker in question doesn't make it clear which of the two is the "Twin". If it's just as feasible that the device teleports the person who uses it to the new location, still alive and themselves, while simultaneously producing an identical duplicate at the starting point, then which one is the "original" person may be impossible to determine.
If the Twin Maker is kept a secret, it will probably be part of The Reveal. Particularly devious characters may exploit the Twin Maker for their own ends, perhaps to create decoys to lure out assassins, or to dispose of an Unwitting Pawn by "tweaking" it mid-way through its creation.
- Neon Genesis Evangelion
- Fate Testarossa of Magical Girl Lyrical Nanoha was developed as a Replacement Goldfish after the originals' death. It didn't go exactly as planned, and her creator wasn't thrilled.
- Self-enforced with Robot. He is actually a deformed human living in a fluid tank, who's secretly been collecting genetic material in order to clone himself. The final product is a normal, healthy teenage boy with the exact same memories and mind as the originaland he immediately goes through with what he'd planned to do in this situation, killing the original.
- The Mauler Twins, the supervillains Robot recruited to make his clone, are a clone and original team who designed the mind-copying process specifically to make it impossible to tell which one is the clone. Apparently one iteration of the pair was able to figure out which one was which, leading the original to lord it over his clone until the clone poisoned him.
- In Transmetropolitan the telefactor speed-grows a clone of the subject and forms a telepathic link between them so the clone acts as a Remote Body while in use. Spider uses it to covertly meet with the President's wife on the other side of the country without the Secret Service noticing him leaving the City.
- In the live-action In Name Only Æon Flux movie, everyone who has ever lived in the past 400 years is a clone of a small pocket of humans left after a worldwide plague. Only a select few Ancient Keepers are permitted to know this.
- In The Prestige, a machine is invented that creates a duplicate of whatever's put inside it, and it's unclear whether it teleports the original away or it creates the copy some distance away. It's revealed that a magician uses the machine as part of his Transported Man illusion, each time drowning whichever one remains in place. (The first time he uses the machine, the Angier who stays in place shoots the one who appears at a distance, meaning the "original" is dead either way.)
- Sean Williams has written several novels (including The Resurrected Man and the aptly-titled Twinmaker) and short stories that explore the use and abuse of so-called "d-mat booths" that work by breaking the person who steps into them down into little bits of data called a "pattern" and then using the pattern to create an exact copy of the person in another location. Everything about the person is the same, down to their thoughts, feelings, and memories, so that those who come out of the booth believe themselves to be the same person who stepped in it, effectively making it a form of teleportation. The Resurrected Man is the origin of the phrase "Murdering Twinmaker", which in the novel is both a nickname for the teleporter and the nickname for a serial killer who uses the data in the sending teleporter to create his own copies, which he murders for pleasure.
- Orson Scott Card's short story "Fat Farm", collected in Maps in a Mirror: People believe that they're signing up for a miraculous procedure that restores them to perfect health and youth. What really happens is that they're cloned, their memories are implanted into the clone body, and the clone leaves believing they're the original while the original is put into a forced labor camp.
- Miles Vorkosigian has one of these in the Vorkosigan Saga. He was created to replace Miles, but when Miles and his family found out they broke the clone out and adopted it into the family. He's treated by everyone as Miles' brother.
- C. J. Cherryh's novel Cyteen explored the difficulties of using cloning to make an exact duplicate. In order to produce a clone genius on par with the original the scientists raising the clone had to duplicate the original's upbringing as closely as possible.
- The title character of Joshua, Son of None by Nancy Freedman is a clone of JFK, whose upbringing and experiences are "managed" in a similar manner by his creators. The plan starts to go off the rails when he discovers this.
- In some of Greg Egan's stories, characters deal with things by imagining a line of continuity from the death of the first copy to the creation of the second, despite the lack of causal connection; this shows up in Permutation City and in Schild's Ladder, and possibly elsewhere.
"I'm embodied, not deranged! If a copy of my mind experiences a few minutes' consciousness, then is lost, that's not the death of anyone. It's just amnesia."
- In Permutation City, after launching Elysium, the Paul left behind on Earth kills himself, apparently having only ever cared about his Elysian copy. Meanwhile, Peer is happy to sign up to become two people, seeing it as a new way of breaking away from the "quintessentially human" experience.
- In the short story "The Extra", the protagonist inadvertently condemns himself by transferring what he thinks are the key portions of his brain to a younger cloned body, not realizing that his consciousness will continue in the old body as well as in the clone.
- Sam Vimes objects to using magic anyway, but in Thud!!, even when he gives in and goes to the wizards for help, he absolutely refuses to use teleportation because he's paranoid about the idea that the person at the other end isn't the same person as the one who was teleported. Considering Rincewind once got badly battered by oncoming debris mid-transit during a teleport, Vimes's fear probably wasn't justified, but the Wizzard wasn't on hand to point this out.
- In James Patrick Kelly's novelette "Think Like a Dinosaur", reptilian aliens give us teleportation, but insist on "balancing the equation" (destroying the original afterward) or they'll cut us off from the network. Normally the original is unconscious, but one is revived after the teleport is mistakenly believed to have failed, invoking this trope in full.
- In the Star Trek Expanded Universe novel Federation, when Zefram Cochrane is first transported aboard the Enterprise, he immediately thinks he is a duplicate of the original, assuming transporters to work like replicators. Instead, a crew member calms him down, explaning that the process works on the quantum level, meaning he is still the original Cochrane.
- Averted in Sergey Lukyanenko's Line of Delirium, where the aTan machine re-creates people after their deaths by replicating their bodies from the previous molecular scan and downloading the stored memories into the new brains. Originally, it is claimed by the aTan Corporation that each re-created person is indeed new, although they are considered to be the heir to the dead person's life. However, it is revealed later that re-creating the same person twice only results in one having a consciousness, while the other is a mindless zombie, only able to passively answer questions and perform routine tasks. This is due to something the aTan people call the "x-factor" that is present in humans and several other races. When a person dies and his or her body is re-created by aTan, this "x-factor" locates the new body and inhabits it, giving this new body the same consciousness as the dead person. For some reason, the aTan Corporation decides to keep this a secret from the general public, only informing the Church of the One Will of their findings. Needless to say, the Patriarch immediately gives full blessing to aTan. After all, it's not every day that someone proves the existence of the soul.
- China Miéville's novel Kraken has a nasty subplot based on this idea, about an Urban Fantasy magician who develops a teleportation spell consciously inspired by Star Trek transporters. He doesn't realise that the method actually kills the original and creates an unaware, perfect copy until the vengeful spirits of his dead former versions start haunting him. The hero finally deliberately submits to this as a Heroic Sacrifice, as it's the only fast enough way to get him where he needs to be to save the world.
- The Goblin Reservation has Peter Maxwell, who was abducted to a mysterious crystal planet and finds, upon his return, that "he" is a duplicate brought to the planet while the original died a week after returning from the original journey in a suspicious accident.
- In The End of Eternity, the eponymous organization considers replicators as undesirable as nuclear wars - because there can be no satisfactory solution to the problems caused by this trope.
- In the Star Trek: Titan novel Fallen Gods, Star Trek transporters are redesigned by the novel's antagonist (a commander of Andorian Intelligence working with traditional enemy the Tholians) in order to create duplicates of a transport subject. Assigned to repatriate officers of the starship Titan to their homeworld to aid in a reproductive/population crisis, he secretly duplicates the reluctant officers and makes off with perfect copies, leaving the originals unaware.
- In The Night's Dawn Trilogy by Peter F. Hamilton the cabal that secretly controls Earth ensure their immortality by creating young clones when they get too old, downloading their memories (editing out anything bad) then destroying the clone. However the protagonists have already discovered that the human soul survives after death, so rather than ceasing to exist those souls would become trapped in an Afterlife Antechamber.
- In MARZENA, Digital Clone = Bremen Mind Merging Chip + Brain Osmosis Infusion on a Blank G-Net AI.
- This is combined with Mental Space Travel in Competitors, where a travel agency promises anyone who signs a contract several years of adventure in space. They explain that the person's body will be duplicated on a distant Space Station, at which point the double can start flying and working, experiencing all the wonders of space adventure, while the original on Earth can track the double's progress through a browser-based online game. Of course, everyone thinks it's all crap. They pass through the door and nothing happens. Their doubles' reaction is of the "Holy shit, it's all true!" variety. The people at the agency don't understand how it works, as the device is provided by their alien benefactors. According to the claim, after 3 years, the double's consciousness is merged with the original's, allowing the original to experience 3 years' worth of extraordinary memories. Then again, life is cheap out there, so not many actually survive so long.
- This turns out to be the case in Knights Of Forty Islands, where children are abducted by a strange man with a camera, who takes their picture, after which they end up on an island chain somewhere. The protagonist meets a girl he knows, who claims to have been on the island for months, except he had seen her mere days before. They realize they're copies, so no one actually misses them or tries to find them. One guy's original is likely dead, as he claims to have been taken while falling out of a window.
- In Illium, "faxing", a means of teleportation utilized by old-style humans, works on the principle of disintegrating the original and recreating them from a pattern scan at their destination. This is how the Firmary can bring back Daeman even after he has been eaten by a genetically-engineered Allosaurus. It basically just recreates him using the scan taken from the last time he used a fax node. There is a hint in the fact that his memories do not include the events leading up to his being eaten, because that was after he was faxed.
- An interesting variant occurs in Worm with Oni Lee. Whenever Lee teleports, his new body is formed at the target destination and his old body continues on for several seconds before dissolving into carbon ash. But those seconds can be a long time in combat...
- Farscape had a subplot of Crichton's twinning. Although in this case, neither one was a copy or original exactly. Crichton really was just duplicated/"twinned" into two identical Crichtons (they play rock-paper-scissors and draw some 100+ in a row). The episode where this occurs explores the trauma involved in the concept in some depth; being twinned just once is shown as quite traumatizing, and most of the people encountered in this episode are hopelessly insane after having lived through being twinned and having their twins killed multiple times.
- They even use this in the next episode to have one twin impersonate the other to "prove" Crichton was never at the scene of an explosion (since he is of course, completely unhurt).
- The rock-paper-scissors thing is referenced later to show how they have diverged from each other, one (having died) sends the other a holographic recording which he closes by offering to play again, throwing rock as the other Crichton throws paper.
- They even use this in the next episode to have one twin impersonate the other to "prove" Crichton was never at the scene of an explosion (since he is of course, completely unhurt).
- Star Trek: The Next Generation had Thomas Riker, William T. Riker's transporter duplicate, created during a pre-show mission when someone tried doubling up the transporter-lock to get a better chance of beaming him off a planet with tons of interference during an emergency. One transport-beam made it to the ship, the other got bounced back to the surface. Nobody realized at the time that they had created two Rikers, one of which was marooned for years as the other advanced his career and went on living his life. Interestingly, Thomas claimed that he would never leave Deanna, as Will has done, even though up until the split they were the same person. This was probably Thomas trying to distance himself from Will, hating that he chose to advance his career instead of maintaining his relationship with Deanna. Also interesting in that technically both Rikers are copies of the original who first went through the transporter due to the way the transporter works, so neither is technically any less real than the other.
- Star Trek: Deep Space Nine: Weyoun has died and been replaced with a clone several times over the course of the series. One episode dealt with two Weyoun clones existing at the same time (one had gone AWOL, so his next clone was activated early). Near the end of the series, he's deeply frightened when the Dominion's cloning facility is destroyed, allowing him to be Killed Off for Real.
- The Outer Limits (1995) made "Think Like a Dinosaur" (see Literature section) into an episode.
- In an episode of Earth: Final Conflict, Liam is implanted with a tracking device by Sandoval at Zo'or's request, as they have grown suspicious of him. In order to allow them to continue their investigation and keep Sandoval and Zo'or in the dark, Street puts Liam into a mini-coma and uses a modified ID portal to create a quantum duplicate of him without the tracking device, although she claims that the universe will eventually erase him out of existence. The duplicate Liam is identical to the original in every way and doesn't seem to mind being the copy. At the end of the episode, he makes a Heroic Sacrifice to save Renee. Just before the Earth-Shattering Kaboom, he sends a message to Sandoval, which confuses the latter to no end, as he knows thanks to the tracking chip that Liam is nowhere near that location. He later questions the real Liam, who has no memories of these events, before dismissing the matter.
- Like many devices introduced in the series, this is never mentioned again, even though it would have been very helpful in many other circumstances.
- Transfer Transit in Dark Matter puts you in stasis and scans you and transmits your data to another planet to construct a clone with a lifespan of three days. At the end of that lifespan the clone, ideally, returns to the facility and their memories are transmitted back to the original you. But, as Six discovered, if the clone dies before returning their memories are lost.
- Live Forever As You Are Now with Alan Resnick: Alan's plan for eternal life revolves around creating computerized clones of himself and other people, attempting to make them as similar as possible to the original person, so when that person dies the clone can take over. It...doesn't really work out.
- Paranoia: Every player character has six identical clones, and when one dies, the next one is sent in to replace it.
- In Dungeons & Dragons Clone spell could be used to create copies of a creature, normally as a form of resurrection when the original is lost completely. Only One Me Allowed Right Now effects implied that it's more than just an identical body, though. Stasis Clone (unique spell from Forgotten Realms) makes the revival of one stored copy upon death automatic and allows to "update" inactive clones. As of 3E the Clone spell simply creates an inert duplicate that the original's soul transfers to at death.
- Eclipse Phase uses Brain Uploading for both pseudo-immortality and most interplanetary "travel". Though unless they were really rich someone rarely gets downloaded into a clone, rather a "used morph" that happened to be lying around at the body bank. Making more than one active copy of a person is fairly easy and highly illegal, but slightly edited copies are sometimes used for a form of real-time interplanetary communication.
- In Hc Svnt Dracones "Digitrans" transmits a copy of your character's genome and brain scan to another planet for growing a clone, then euthanizes the original. You can make arrangements to sell your organs to recoup some of the cost.
- In Sonic Heroes, at the end of Team Darks story, Rouge and Omega stumble upon a room full of Shadow clones sealed in the same kind of sleep as Shadow was at the beginning of the game, implying that Shadow may also have been a clone, especially given that he seemingly died at the end of Sonic Adventure 2. In Shadow the Hedgehog, however, Eggman confirms that the Shadow going through the events of those games was the original all along.
- The "Immortality Through Cloning" version is used as a plot point and gameplay mechanic in Destroy All Humans!. The reason the Furons are harvesting human brains is because it contains a strain of DNA vital to their cloning process, and every time you die in-game, your name increases by one digit. There's even a level about recovering your own remains.
- In the Star Trek: Armada games, Nebula-class ships have a special ability called the "Gemini Effect", which temporarily creates a duplicate of the target ship. With some quick thinking, this ability can be used to get free resources by duplicating a vessel and then scrapping the duplicate for parts. The game designers, apparently, did not think of this possibility.
- The Horatio faction in Endless Space. Horatio the First, an androgynous, beauty-obsessed narcissist, left society to set up shop on a planet by himself, where he found Imported Alien Phlebotinum. He then proceeded to clone an entire society of himself and then decided that the rest of the universe could only be improved by the presence of more of his beauty. Their "hat" is high population growth and density.
- Heat Signature: All teleporters work on this principle.
- The Fast Travel stations in Borderlands 2 may work like this. One of the callouts from the New-U station mentions that your new body is just a reconstruction of your original body that died the first time you respawned. And since fast travel stations also incorporate this tech, it's likely they work on the same principle.
- In System Shock, the main character can perform a DNA upload in a quantum entanglement booth (called a "Quantum Bio-Reconstruction Machine" in System Shock 2). Then, if they die, they are cloned at the booth with the stats they had while they were there last, like a checkpoint.
- Towards the end of the Sith Inquisitor storyline in Star Wars: The Old Republic, the Inquisitor's body starts dying quickly (not that it affects the gameplay) as a result of acquiring too much power from absorbing Force Ghosts too quickly, so you have to find a device (the Mother Machine on Belsavis) that basically replaces your entire body with a genetic duplicate, transferring your consciousness to it.
- The death mechanics of the EVE Online player characters are based around this: Once you are about to die, your escape pod kills you and awakens a previously contracted copy of yourself somewhere else, that has a printed brainscan of your life's memories up until the very moment of death.
- The Cloning Bay introduced in FTL's Advanced Edition update replaces the standard medbay on certain ship layouts, and is also available for purchase in in-game shops. True to form, it creates a clone of any deceased crew member when they die, with a small penalty to their skill experience. It also takes advantage of "micro-cloning" technology, which heals a small amount of all crew members' health each jump.
- Path of Exile: the Bodyswap spell causes the original to explode and a clone to appear by using the mass of an unfortunate enemy or corpse.
- In SOMA, this trope (Specifically, how it relates to human consciousness) turns out to be central to the plot: the protagonist finds himself "transported" to an underwater base in the post apocalyptic future after a brain scan due to the scan having been donated to science and made into a standard template by his long deceased original self and the base's malfunctioning AI experimenting in creating new forms of life. Later on, he believes he is transferring his consciousness to another body in order to get to a deep sea trench without being crushed by the pressure and apparently succeeds, only to discover that actual transfer is not possible: only copying, which now means there is another Simon (that the player might decide to Mercy Kill or spare). At the end of the game, he experiences the flip side of this, when he believes he is transferring his consciousness to a paradisaical virtual world...only to remain in the same place, since another copy was created inside it, meaning he is now trapped forever in the bottom of the ocean.
- While it's not touched upon by the game itself, Wendy from Don't Starve mentions this whenever she teleports. Surprisingly, she doesn't do so in any dialogue involving revival altars or meat effigies, which are much more in line with this trope.
- VVVVVV has a number of teleporters, and while it doesn't really explore the mechanics or morality of them (they're just a gameplay mechanic), one of the rooms containing a teleporter is named "Murdering Twinmaker" as a direct reference to the trope.
- In Freefall robots don't care much about backups. Want to know why?
- While actual teleportation is possible in Schlock Mercenary, the wormgate network used for it prior to the invention of the teraport also created clones of those who used it without the traveler's knowledge.note This became a major plot point when it turned out the Gatekeepers were interrogating and executing the clones, and using the information gained to control the galaxy's wealth and suppress rival teleporter technology. The current Kevyn Andreyasn is a clone created in this manner shortly before the original made a Heroic Sacrifice, who simply took over his original's life without a single care about the existential issues. He did put it on his resume, though. Similarly, later on Schlock is killed off, and a new Schlock is created to replace him. The new Schlock thinks it's kind of cool, "but not cool enough to do twice." Eventually the technology to do this comes into common use throughout the galaxy. Suddenly everyone starts cheating death through cloning, prompting a few identity crises. Captain Tagon's clone is quite emphatic that he's not the same person who carried a ship-to-ship missile into a enemy beachhead, because he was produced from a mind backup taken around 45 minutes earlier.
- Existential Comics addresses this in the first comic.
- The teleporter in Red Space Blues has a significant delay between copying and "clean-up", which is rather messy too.
- In Grrl Power Harem's super powers are teleportation that doesn't necessarily disintegrate the original, and a Hive Mind with all her copies. Most of the time she has five of herself with different hair colors and outfits.
- In El Goonish Shive, touching the Dewitchery Diamond while under a "curse" (broadly defined) results in two almost identical individuals: one without the curse and one under the curse's effects as if it's a part of their default form. "Curse" in this case includes any spell that changes one's appearance, abilities or behavior.
- A mysterious alien artifact in the space arc of Arthur, King of Time and Space appears to have this as its only function. In-universe, the reason for this is unknown, out-of-universe it's to set up the space arc version of the False Guenevere story.
- In the Mortasheen universe, Wreathe uses portal technology, which preserves the teleported person intact but is incredibly inefficient. Meanwhile Mortasheen utilizes teleportation that makes a twin of the user somewhere else and destroys the original. Mortasheen being what it is, no one there is bothered by this and the twin is considered and treated as the original. Wreathe, however, is revolted.
- This how the Auds from Phaeton have survived for so long, and why they look like kids, of course it didn't go too well for one of them.
- Canadian animator John Weldon's terrifying short, To Be: In it, a scientist is demonstrating his new "Murdering Twinmaker"-style teleporter. The heroine claims that the machine is immoral, and to assure her that there's no need to worry, he agrees to delay the "murdering" part of the machine by a few minutes. The original and the clone come out and meet each other, they play a game of chess, and then each fights tooth and nail to push the other into the machine. She just grabs one of them and helps the other scientist push him in as he kicks and screams and begs for his life. They end up shutting him in with his arm slammed in the door and nuking him, causing his arm to visibly disintegrate. Then it gets quiet. The surviving scientist realizes the immorality of such a device and walks away, but the heroine feels guilty and decides that she has to atone for what she did, and enters the machine.
- In one Æon Flux episode, the titular character's archenemy and lover creates a clone of her. The clone and the original meet and conspire against him. In the end, one of them gets gunned down in front of Trevor. It wasn't the clone.
- The Venture Twins have this kind of immortality in The Venture Bros., but they're unaware of it. As of Season 3, when the clones were used as an army during an attack on the Venture compound, this is no longer true.