Maybe it's to explore a new world. Maybe it's to be better and stronger than before. Or maybe it's a mistake and it leaves the person Trapped in Another World.
Regardless of why, this trope involves a person who can be (or who is) downloaded into a remote interface to interact with others or another world better (or at all). This other self is otherwise an Empty Shell that does nothing. Sometimes when the remote version of himself is damaged or killed, he is hurt/killed back at home or in 'reality', but the idea is, while the main body 'sleeps', a different body acts and works remotely by his commands. This is used to play games, interact with computers, or interact with an alien world.
Unrelated to We Are Our Avatars.
Examples:
- Avatar: The titular avatars are Na'vi clone bodies that humans can remotely control to explore Pandora freely (something necessary since they can't breathe Pandora's atmosphere), as well as to earn the Na'vi people's trust and hopefully reach a diplomatic conclusion to their war. The protagonist agrees to controlling an avatar because he's paraplegic, and thus wants an avatar so he can walk again, temporary as it may be.
- This is somewhat of a plot point in John Carter: John wasn't actually teleported to Mars, just a carbon copy controlled by his consciousness.
- The Matrix does this with the people who plug in.
- The plot of Surrogates has this happen on a global scale in everyday life — everyone uses the titular robot bodies to go around, while their real bodies are kept inside their homes.
- Animorphs: In The Ellimist Chronicles, the Ellimist (who at that point is a Hive Mind group of Sapient Ships) downloads a limited copy of his personality into an Andalite body and lives among them for some time, even having a mate and children. Meanwhile the rest of him is still aware and active, since he has a higher consciousness at this point.
- The central conceit of Dinoverse is a form of Intangible Time Travel where characters' minds are converted into "thought-wave energy", sent back in time, and immediately possess the bodies of dinosaurs, able to communicate through weak Psychic Powers. In the first book, the first four are sent a message from the far future informing them that unless they find a way back themselves, their bodies remain comatose for decades; no one else can recover them.
- In Haruhi Suzumiya, this is what Yuki Nagato and the remote interfaces for the Data Thought Entity and their rival the Canopy Overmind are.
- Done via Astral Projection in John Carter of Mars.
- The Night's Dawn Trilogy: Ione Saldana and a couple of other characters download their own personalities into bioengineered Super Soldiers to fight wars. Ione lives in a space station which she herself has never left, and the other characters are often dead. Not to mention Edenists' downloading of personality into habitat 'multiplicities', preserving their memories for centuries after their bodies are dead, or the general effect of possession. Okay, fine. The entire yarn wouldn't exist without this trope.
- The Otherland books are set in an AI world, so most of the main characters are avatars of assorted real-life people. Orlando Gardiner, in particular, has progeria, so sometimes considers his virtual life more real than his home life. Eventually, his body dies, and he becomes a permanent inhabitant of the virtual world.
- In Safehold, Nimue Alban's fabulously wealthy father bought her a fabulously expensive PICA — a robotic body capable of temporarily hosting a human consciousness. Nimue mostly used it for extreme sports, but it was... fully functional... If You Know What We Mean. Merlin explores that aspect later, If You Know Wha— you get the idea.
- The Ship Who...:
- During Dramatic Mission, a trade is made between advanced jellyfish-like aliens who live on a methane-ammonia world and a human-based interstellar federation — alien technology in exchange for a staging of Romeo and Juliet. However, it has to be one the aliens can fully appreciate, so they first give Central Worlds the technology to beam the actor's brains into alien "envelopes" that have been prepared for them.
- In The Ship Who Searched Tia, despite being quite happy as a Sapient Ship, is unsatisfied by non-standard gestures of intimacy and wants to be with Alex. She was paralyzed from the chin down as a child and can't be removed from her life support capsule, so instead, she has a Ridiculously Human Remote Body commissioned. It's got a limited range and while it's active, it uses so much of her processing power that the ship that makes her "real" body is inert, but she's got plenty of time to spare for this while docked.
- The heroes of Stargate Atlantis encounter a good Replicator living on Earth. Although she helps them, she is too dangerous to remain free, so they place her in a realistic virtual world where she may live as she pleases.
- Id_Entity is the manhwa version of .hack, except it comes with a mode where you can actually play as you sleep, through some kind of science babble about the subconscious mind.
- .hack is normally about an MMO played with a head-mounted display, but players have their minds drawn into their avatars whenever the game's undocumented features kick in. That said, even when the game is operating normally, characters often act as if this trope were in effect, particularly in anime and manga stories. As the franchise progresses, the effects of being trapped in the game escalate towards nearly supernatural heights.
- This is ubiquitous in Ghost in the Shell; it's either remote interface or the person's actual brain in the avatar's body.