Reese: You go naked. Something about the field generated by a living organism.
Dr. Silberman: Why?
Reese: I didn't build the fucking thing!
Time Travelers are often prevented from bringing along any modern technology when they go back in time. When they arrive in the past, they have to rely on the things available during that time period.
The reasons for this vary. Sometimes the time travelers simply want to avoid changing the timeline too much, and they realize that, say, leaving a modern gun behind in the middle ages could create all sorts of problems. Other times it's due to a limitation of the Applied Phlebotinum used to travel through time. In the latter case, the time traveler often arrives naked and has to find clothing somewhere. In other cases, the time travel may simply have been a surprise and they weren't prepared.
Sometimes the inverse is seen, where it's not possible to take anything from the past back to the future. (Sometimes this is justified by the claim that, for the object, the future doesn't exist yet.) Since it's otherwise not much of a dramatic limitation, this version usually only comes up in stories where a time-traveler is trying to save something (or someone) from being destroyed in the past. Not to be confused with the only saying "You can't take it with you", referring to when you die.
- Chao Lingshen of Mahou Sensei Negima! solves this by improvising with what she has in the current timeline. She still ends up being a genius inventor.
- Averted in The Ambition of Oda Nobuna where Sagura Yoshiharu had his cell phone with him when transported back 450 years in time. That cell phone is a Chekhov's Gun.
- In Strike the Blood, Reina arrives in the present naked and has to steal clothes. She could bring her magic spear with her because she can create and dismiss it with her powers. When she returns to her time, she vanishes and her stolen outfit falls to the ground. She arrives in her home naked and quickly puts on a bathrobe.
- Inverted in Happy Heroes; after they return to the future, anything the Heroes leave behind vanishes.
- And one of the Dark Horse series of Terminator comics had a group of T-800s sent back to the past accompanied by a very unfortunate human in whose abdomen they'd surgically implanted future weapons prior to coming back. They ripped him open upon arrival and were good to go, rayguns-wise. Why Skynet doesn't do this more often (or just wrap the weapons in synthetic flesh, the same way it does the T-800 exoskeletons) is unexplained.
- The original War Machine armor was destroyed in this manner after Rhodey was caught in a "time-quake" while traveling back to the present from World War 2-era Germany.
- In The Infinite Loops, carrying things across the Loops requires either that the item be soul-bonded to a Looper (usually occurs with powerful magical artifacts), or that it be stored in a Subspace Pocket at the time the Loop resets. It is technically possible (Depending on the Writer anyway) to put living beings into a Pocket, but this is generally discouraged for obvious ethical reasons.
- Terminator is probably the most famous example of the "arrives naked" version. However, the titular killer robots are able to travel back in time because they're covered in living tissue. Presumably, the liquid metal that more advanced models use is able to mimic living tissue closely enough to work.note
- Averted in the third movie, where the T-X has an energy weapon built under her liquid metal exterior.
- 12 Monkeys is an example that's due to limitations of the technology. However, it seems like objects can pass through so long as they're inside one's body - James Cole is always Naked on Arrival after time travel, but at different points in the film he deliberately brings a spider specimen to the future by swallowing it, and accidentally brings a bullet with him to the present by being shot in the leg in the middle of World War I.
- In the movie Timeline, the time travelers deliberately do not to bring anything modern back because they don't want to pollute the timeline. Except for one bloody idiot, whose insistence on bringing along a few grenades screws everyone when he accidentally blows up the transfer point. In the original book, they bring translator earpieces along, but no other modern technology.
- In Teenage Mutant Ninja Turtles III, the magic scepter that was causing the time travel caused the people on each end of the time warp to switch places, with all their possessions staying in their own time. Michelangelo notices this when the Japanese nobleman appears in April's clothes, and makes a point of donning some trunks before he and the other turtles go back in time to retrieve April so that the person he switches with doesn't arrive naked.
- Strangely, as he's the only one who does this, the four time-displaced samurai who switch places with the turtles show up in their historical underwear instead of naked (it IS a PG kid's film after all)... except Michelangelo's, who shows up just wearing the trunks like he had been going commando under his armor.
- Henry in The Time Traveler's Wife, who has a disease that causes him to spontaneously time travel. He cannot bring anything that is not part of him, like clothes, money or even dental implants.
- In The Pendragon Adventure, the Travelers never bring anything from one territory to another, in fear of destabilizing the territories. Later subverted by Saint Dane, who gleefully mixes the territories and increases the technological level of the Earth territories as part of his increasingly complex Gambit Roulette. Bobby eventually gets fed up and brings in technology from different territories in order to defeat Saint Dane's schemes. This does not end well.
- Doomsday Book and To Say Nothing of the Dog, by Connie Willis use the reversed version: time travelers can bring things from the future to the past, but not the other way round. ...except for things that would have been destroyed shortly anyway.
- And, of course, a cat, because the cat was going to drown anyway. Except it wasn't, and the net allowing it to go through was a Batman Gambit by time itself to cause a cathedral to be rebuilt in a certain spot hundreds of years later, apparently.
- In the Discworld book Night Watch, it's physically impossible for time travelers to take anything with them that doesn't belong in the destination time. Thus, a character who's changed his clothes while back in time will return to the future naked, it's a good idea to eat when you get back because the food you ate then stays there, et cetera. This is not, in fact, always true — one of the time travelers brought his armor with him — but it's a very useful lie. The issue seems to be one of available power and the fact that sending him back is a bit of a rush-job:
Lu-Tze, explaining to a baffled and annoyed Sam Vimes: "We don't have a damn great thunderstorm and we don't have enough stored time. It's going to be hard enough making sure you don't come out a thousand feet in the air."
- In Spider Robinson's Time Pressure, the time traveler arrives naked (except for her computer headband thing) and bald because of the limitations of the time machine. Time travel in some of the author's other books has similar limitations, such as an inability to bring living and nonliving things at the same time.
- In Alastair Reynolds' novel Century Rain a force-field prevents travelers to the alternate-1950s earth from bringing through any complex technology at all - a big problem since it opens underground. They manage to get a jackhammer through by disassembling it and reassembling it on the other side, and running a hose through the field to an air compressor.
- The first Doom novel has this, not when time-travelling, but when teleporting. The characters worry about whether it includes things like intestinal flora.
- In a spin on this, the setting of Garth Nix's Old Kingdom trilogy is hostile to modern technology. Things that work in Ancelstierre, like telephones, machine guns and cars, cease to function once they get north of the border — or even just close to the border, if the wind is blowing from the north. Things made by machines also tend to fall apart. As a result, travelers to the Old Kingdom have to be prepared to bring only things made by hand, and the border guard know how to use swords and bows as well as firearms.
- A similar version happens in Vernor Vinge's A Fire Upon the Deep. All sorts of amazing technology works when you're in the outer parts of the Milky Way galaxy, but as you travel inwards they will begin to fail in order of most advanced, as well as faster than light engines working less and less efficiently until failing entirely as well. Eventually, as you get close to the center, even higher brain functions begin to fail.
- The Company Novels by Kage Baker use the reversed version: time travel is only possible into the past, and things of the past can't be carried back to the present (their future). The Company gets around this using a very, very elaborate Write Back to the Future system.
- Though it involves dimensional travel instead of time travel, in The Great Game series by Dave Duncan, Strangers can't take anything with them to other worlds. This includes not only their clothes, but dental fillings, prosthetics, and possibly the contents of their stomachs.
- Normally averted in Time Warp Trio. However, when they go back to the time of the cavemen with the intention of bringing back modern tech, they're left with nothing but their glasses, hat, and a straw.
- This is because they tried to take too much back. Also, another book mentions trying to take too much knowledge from the future to the present can be bad.
- Subverted in Robert Charles Wilson's The Chronoliths, where people don't travel in time, but a future leader sends back giant monuments to his victories from the future. These monuments are also extremely destructive weapons ("city killers") when they arrive.
- Time travel is a major part of the plot in the sixth Artemis Fowl book. Due to the extremely unstable nature of the time stream, and the fact that the demon sending them back in time (No. 1) is a novice, he recommends that Artemis and Holly strip down, lest your clothing fuse to your skin. They are both understandably embarrassed, but manage to strip down to their underwear (Artemis is wearing red Armani boxers and Holly is wearing a standard issue LEPrecon one-piece).
- Their embarrassment forms part of the Unresolved Sexual Tension between the two in this book.
- In Dinoverse no one can take anything with them. Including their bodies. Instead the bodies of these intrepid time travelers fall into comas and their minds go back and possess the bodies of large, complex vertebrates - as the series' title suggests, everyone who time travels in the series ends up in a dinosaur. When they get to go home, each character again can't take anything with them, although in one case when a human and an allied dinosaur died in the same instant at the same place having the same kind of self-sacrificial goal, both their minds ended up sharing the human's body. Sadly, this is never fully explored.
- The Dinosaur Cove series is like this. The kids can't bring anything back to the present with them. They can take their info gadgets back in time with them, though.
- Played with in the Time Scout series- if it can be carried through a portal into the past or future, then it can travel through time, unless it already existed somewhere else at the destination time period. If that's the case, then the transported item or person simply ceases to exist (sending people on a free "holiday" to a date after their birth is a popular murder method with organised crime). Presumably the gold, jewels and other artefacts successfully brought Uptime were/would have been wholly disintegrated in the mean time.
- In the Time Machine gamebook series, the rules of time travel specifically prohibit the player from leaving behind any item from a future epoch, and breaking the rule can supposedly result in being trapped in a time loop.
- Originally in TimeRiders, the team had to be underwater while time travelling to avoid taking a chunk of the concrete floor with them to the past, as well as... in their underwear. Rashim's method seems to avoid that, but they still can't bring anything modern.
- Inverted in the Dinosaur Cove book series. The kids can bring technology with them, like the Fossil Finder, but can't bring anything from the past back to modern times. A Ginkgo leaf one of them tries to bring back crumbles to dust.
- The Neverending Story: A non-time travel example. Bastian cannot leave Fantastica with anything the Childlike Empress gave him or that he received in Fantastica. This means his clothes fell off him and he changed from the Oriental Prince look to his normal look as both were given to him by the Childlike Empress.
- The early Red Dwarf episode "Stasis Leak" had an inversion where the crew could take things to the past fine, but couldn't bring anything back with them. (A bar of soap used to try it out crumbled to dust; the implication was that — at least using the stasis leak method — anything brought Xty years into the future instantly aged Xty years.) When Rimmer says he wants to bring his past self back, the Cat agrees for once. (Rimmer takes a few moments to figure this out.)
- Sam in Quantum Leap is never able to take anything with him during his leaps because he was being shuffled around by a "higher power" that probably didn't want him messing up the timestream with artifacts while he was supposed to be fixing it.
- Brief subverted in "The Leap Back", when Sam and Al unwittingly switched roles as Leaper and Observer; for unspecified reasons, Al retained the handlink control for the Accelerator, requiring Sam and Al to Write Back to the Future so that Sam could get out of the Imaging Chamber
- A non-Time Travel version in the series Forever. Whenever protagonist Doctor Henry Morgan dies, his body vanishes and reappears naked in the nearest body of water, with his clothes apparently vanishing along with any blood he left at the scene. The first time we see him reappear, Henry is immediately arrested for indecent exposure, and it's implied that this happens a lot.
- In the pilot episode of Terminator: The Sarah Connor Chronicles, the human resistance gets around this by sending an engineer back to the 1960s, where he builds a plasma rifle and time machine from contemporary equipment and stashes them in a bank vault. However, it's played straight later in the episode, when Sarah, John, and Cameron send themselves forward to 2007 and wind up naked on a very busy highway. Double Squick points for this one, considering that Sarah is John's mom.
- The Outer Limits (1995): A variation in "In Another Life" as it involves travel to an Alternate Universe rather than Time Travel. When the various alternate versions of Mason Stark are transported to the Eigenphase Industries CEO Mason's universe by the Quantum Mirror, they arrive naked.
- Played with in The Adventures of Brisco County, Jr. episode "Bye Bly", when a woman from the distant future arrives naked because long-distance time travel is safer without clothes or jewelry. It's not a strict rule and her mission is to return the Orbs to her time, but she departs as naked as she arrived.
- In the Forgotten Realms, items being sent back in time won't make it if they are more technologically advanced than the destination time period. The same goes for spells. It's also impossible to take anything from the past back to the future with you.
- The Demoreans in Timemaster note have innate time travel abilities. However, those abilities only move the Demorean. Since most of their plans require advanced tech, they have to get time-traveling renegades to move their gear for them.
- In the text adventure game Time Zone, any object taken back to a time before it was invented vanishes from existence.
- In Day of the Tentacle, the damaged time machine cannot send living creatures and larger objects, so the player has to find ways around this problem, such as putting a hamster in a freezer and then microwaving it in the future, and putting a sweater in the dryer with 200 years' worth of quarters (which shrinks to doll-size).
- In Pokémon Gold and Silver, the time machine used to trade with Pokémon Red and Blue will, rather obviously, only allow you to trade first-gen Pokémon with attacks that were available in the first generation (e.g. trading a Cubone will be okay so long as they don't know Bone Rush).
- Braid probably qualifies for this; you literally can't take anything with you that isn't made immune to fluctuations in the time-stream, and this also applies to any creature (including yourself) that isn't insulated against the time-stream. While convenient in some ways (you can leave yourself the key to a door in one spot, rewind, and then go do something else before going back to reclaim it) it's also rather awkward in others even if it is rather amusing the first few times, to watch a regular key go skipping backwards just because you walked in the wrong direction.
- The Styx Time Gate in the Star Ocean series prevents anyone from taking modern technology (or indeed, anything more than clothes) into the past. It's never explained why this is the case, or what happens if you try.
- The Japanese guide books explain that it is not technology per se that is blocked, but rather metallic objects. The Time Gate is an electromagnetic phenomenon, and metal or electronic objects would interfere with its operation much like when a person wears metal jewelery during an MRI scan. Carry metal or electronics with you, and at best you'll arrive in a different time and place from where you intended. At worst you'll be dead.
- The cardinal rules of time travel in The Journeyman Project, besides not interacting with anyone not from one's own time, is not taking any important items or leaving any items in different time periods. Stealing bolt cutters from the 3000s to use in the 2000s is OK, though. Just don't leave them there.
- Even the temporal terrorist Elliot Sinclair adheres to this rule, although for pragmatic reasons rather than a desire to preserve history (which would run counter to his goals): his three robots are all designed to self-destruct in the event they are disabled and presumably captured. For the most part, however, this rule is adhered to only as a matter of coincidence and is frequently ignored, especially in the second game.
- Invoked by in the main scenario of Half-Minute Hero. If you decide to replay a level, you can't equip any items that you've earned from later levels (the Time Goddess will tell you that doing so would create a Temporal Paradox). If you attempt to equip an item that's been struck out in the equipment menu, you'll start the level with nothing in that equipment slot.
- In Duke Nukem Zero Hour, when traveling back in time to the Wild West, it's implied that Duke arrives in the buff. Invoking The Terminator, Duke asks the local for his clothes, boots, and horse before deciding he doesn't need the horse.
- Discussed in Manly Guys Doing Manly Things: early on, the squad thought it was true, then they noticed that Commander Badass's body hair didn't disappear. When they find out that animal hair can apparently time travel safely, they started demanding to the scientists that they get clothes. The scientists, annoyed that the squad was back-sassing them, gave them embarrassing Christmas onesies made of wool.
- The time traveling boat in possession of the SCP Foundation does not allow anything to be taken out of its time. If you try, it will change it to something that fits the time its in.
- Vandal Savage's time machine in Justice League works with a sort of inversion: You can't go back to a time where you already exist, but you can send any objects through that you want. Being an immortal caveman, Savage can't go back himself, so he sends a laptop to himself during World War II in order to win the war for Germany.
- In a later episode, Superman gets blasted into the future. It turns out Vandal Savage had some grand master scheme that went awry, killing everyone except himself (Immortal Magnificent Bastard caveman Nazi, remember). Savage regretted ruining the world, and he and Superman got another time machine he had working; since Superman was gone, he could travel back in time long enough to foil Savage's plot.
- In Teenage Mutant Ninja Turtles: Fast Forward, the turtles and Master Splinter are abruptly zapped to the future. Their weapons and cloth— er, accessories get left behind. No explanation is given, and it doesn't happen on the return journey, though they voluntarily leave future technology where it belongs.
- Done oddly in the Steven Universe episode "Steven and the Stevens"—Steven is riding his scooter when he accidentally time travels a few minutes into the past; for some reason, his scooter and helmet get left behind, but none of his other clothes or possessions.
- Lampshaded and subverted on The Grim Adventures of Billy & Mandy in the Big Boogie Adventure movie. Billy asks his time-traveling future self if he's naked because it's impossible for clothes to time-travel, but Future Billy replies that he was actually going naked willingly because he liked to feel the breeze on him.