History Main / TheTimeTravellersDilemma

* [[spoiler:Edeard]] encounters this in the ''Literature/VoidTrilogy''.

* In ''The Time Ships'', the Time Traveller's second trip into the future sends him to a completely different world from the one he remembers. He concludes that with every use of the time machine he is potentially committing murder on an unimaginable scale and vows to prevent himself from ever creating the machine. Later subverted when it turns out that the many worlds model is in effect.

* The second chapter of ''VideoGame/FateGrandOrder'', "Cosmos in the Lostbelt" is a "ThereCanBeOnlyOne" scenario with {{Alternate Timeline}}s competing to be the only reality possible. The protagonists are fighting for the original timeline; but as they visit each of the others, they make friends. Those friends will eventually have to be RetGone.

* The second chapter of ''VideoGame/FateGrandOrder'', "Cosmos in the Lostbelt" is a "ThereCanBeOnlyOne" with AlternateTimeline competing to be the only reality possible. The protagonists are fighting for the original timeline; but as they visit each of the others, they make friends. Those friends will eventually have to die via RetGone.

* The second chapter of ''[[VideoGame/FateGrandOrder]]'', "Cosmos in the Lostbelt" is a "ThereCanBeOnlyOne" with AlternateTimeline competing to be the only reality possible. The protagonists are fighting for the original timeline; but as they visit each of the others, they make friends. Those friends will eventually have to die via RetGone.

* This is the main focus of ''Series/{{Continuum}}''. The protagonist is thrown back in time with a group of WellIntentionedExtremist s who wish to avert the dystopian future. She is faced with the dilemma of either trying to stop them and preserve her future at any cost, or trying to make the future a better place by preventing historical disasters and/or preventing murders. However, there are several added hurdles:

Related to ExpendableAlternateUniverse, TheStoryThatNeverWas

* ''VideoGame/LifeIsStrange'': [[spoiler: Episodes 3 and 4 deal with this. Max going back and saving Chloe's father's life comes at an incredible cost to Chloe and her family.]]

** And played relatively straight anyway once everything starts going to pot (Baal dies, snakeheads attack, Earth in deep trouble). Apparently, ''Earth'' humans (as opposed to "alien" humans) living as slaves under the Goa'uld is not to be thought of - and we'd be better off never existing in the first place.

** [[AvertedTrope Averted]] in ''Megamorphs 3''. Some things in the altered future may have been better, many things were worse, but in the end when Rachel asked Cassie if they fixed everything, all Cassie could say was that "they put it all back."

** [[MyFutureSelfAndMe Admiral Janeway's]] plan in the finale is to send Voyager home NOW. Captain Janeway points out that she did get Voyager home after another sixteen years. The plot takes over before they get too philosophical, to the disappointment of many watching.

** Mentioned and averted by way of Q. Picard's artificial heart is damaged and he's about to die, so Q gives him the opportunity to change his past to prevent the injury that led to him getting the transplant. Picard worries that any action he'll take in the past could have disastrous consequences, but Q brushes him off with, "Nothing you do will cause the Federation to collapse or galaxies to explode. The only life at stake here is yours. In short, you're not that important."
** Of course, while it doesn't have disastrous consequences for anyone else, the consequences to Picard's own life after not getting in the fight that caused the injury are so bad he immediately asks Q to change it back even if he does die. So averted on a galaxy-wide scale, but definitely present in his own life.
* An episode of ''Series/StarTrekDeepSpaceNine'' has the Defiant crash on a world populated by the crew's descendants (and a future Odo), thanks to a time loop. The characters decide they have no choice but to make sure these people live, and prepare to trap themselves in the past. [[spoiler: Unfortunately, future Odo couldn't stand to let Kira die again, so he screws with the ship, allowing it to escape and erase the entire colony.]] Kira doesn't take it well.

** The scandal surrounding Creator/JimmySavile turns [[Recap/DoctorWho1985JFIGSAFixWithSontarans "A Fix with Sontarans"]] into this for the Doctor and Tegan.

Related to ExpendableAlternateUniverse.

* Handily averted in John Birmingham's ''Literature/AxisOfTime'' trilogy, where a multinational fleet from the 21st century ends up in the middle of WorldWarTwo with no way to get back. The question is moot, as the appearance of the fleet results in a battle between them and the American task force heading for Midway. By the time the main characters figure out what happened, history has already been affected in a major way. Also, according to the novel, the characters know they're not really in their own past but in an alternate reality, so any changes they make will not affect their own timeline. For bonus points, Einstein himself confirms this.

** Averted in the episode "The Savage Time", where Alternate Batman doesn't like living in an authoritarian regime after the Allies lost WorldWarTwo.

** Played straight in the episode "Timeless", in which Harry Kim is driven to SetRightWhatOnceWentWrong, a mistake on his part which killed the crew except for him and Chakotay who were in the Delta Flyer, but both Chakotay and his girlfriend know that this will cause them never to meet. Starfleet also saw it as dangerous and sent [=LaForge=] to stop them.

* The YoungAvengers team was started by the time-traveling villain Kang the Conqueror, who got a look at what he was going to grow into and ran away to our time to try and avoid growing into him. Which he did apparently succeed in, but unfortunately no Kang meant that none of the many fights he'd had with ComicBook/TheAvengers over the years and in some way that lead to almost all of them being killed, the small amount of the alternate world we see looking pretty dystopian, and the members of his team who were children of Avengers members (except for the daughter of the one whose death might actually have been ''prevented'' in the new timeline) fading out of existence. He realized that [[ButNowIMustGo he had to go.]] Although we've found out since that he's still time-traveling trying to find a way to avoid becoming a villain, he's just looking for a way that won't wreck things for everyone.

* The ending of ''Film/TheButterflyEffect'' invokes this trope: [[spoiler: The main character goes back to the beginning, and ends his lifelong friendship/love (depending on the timeline in question) with the female lead before it starts. It works.]]

* Discussed and averted in ''Literature/IslandInTheSeaOfTime'' and ''Literature/SixteenThirtyTwo'', both novels involving the permanent transplantation of a modern town to the past. They came to the conclusion that it was a once-in-a-universe cosmic event, so they were astronomically unlikely to go back, therefore they didn't have to worry about changing the future because they'd already changed it by their very presence.

* ''Literature/TheRifter'': Faced head-on. John, by going to Basawar at an earlier point than the point where he got the key to the gates from Kyle, changes history (and creates an alternate version of Kyle who never traveled to Nayeshi and lost the key); on the whole, the new history is for the better (thanks to American liberalism, the power of love, and perhaps the providence of Parfir), but bad things happen too -- for example, John destroys northern Basawar and all its living things, which wouldn’t have happened in the original time.
* Handily averted in John Birmingham's ''Literature/AxisOfTime'' trilogy, where a multinational fleet from the 21st century ends up in the middle of WorldWarTwo with no way to get back. The question is moot, as the appearance of the fleet results in a battle between them and the American task force heading for Midway. By the time the main characters figure out what happened, history has already been affected in a major way. Also, according to the novel, the characters know they're not really in their own past but in an alternate reality, so any changes they make will not affect their own timeline. For bonus points, Einstein himself confirms this.

*** The series steadfastly refuses to explain how exactly time travel works, meaning the characters have no idea if they can change the future or not.
*** The protagonist begins the series believing that while her time isn't perfect, it still is worth saving. That is until she is forced to reassess her world and the horrible things that take place there.
*** If the future does change, then her son, husband, and family will be erased from existence.
*** If the future can be changed, then it changed the moment the time travel occurred.

* ''Series/{{Lost}}'': Several have tried to save the past...and ''all'' fail miserably and ''cause'' the event, since everything that has or will happen has already happened. Most notably, Daniel's attempts to [[spoiler:reset time so that 815 never crashed by stopping the Incident]] not only results in [[spoiler:his death]], but probably ''caused'' the Incident, since [[spoiler:we see Pierre lose his arm]], a event referenced in the very first episode with him in it.
* Acknowledged and arguably justified in an episode of ''Series/{{Buffy|the Vampire Slayer}}'', involving not time travel but alternate realities. In the Season Three episode "[[{{Recap/BuffyTheVampireSlayerS3E9TheWish}} The Wish]]", Cordelia wishes that Buffy had never come to Sunnydale, creating an alternate reality in which the town is overrun by vampires. Alt-Giles figures out how to reverse the effect, but at the last second, the demon responsible for it tries to stop him, asking why he thinks the alternate (original) universe is any better than the one he knows. Giles' response? "Because it has to be."
* ''Series/DoctorWho'':
** Done beautifully in the episode "[[Recap/DoctorWhoS30E2TheFiresOfPompeii The Fires of Pompeii]]". The Doctor is saddled with the choice of not setting off Vesuvius, thereby saving Pompeii, or sending those people to their deaths in order to keep history intact [[spoiler:and to keep the Pyroviles from conquering Earth. Finally, with support from Donna, he sets off the volcano.]]
** Comes up again later in "[[Recap/DoctorWhoS30E16TheWatersOfMars The Waters of Mars]]", only this time, [[spoiler:The Doctor changes history by choosing to intervene.]]
** Turns up even earlier in "[[Recap/DoctorWhoS12E4GenesisOfTheDaleks Genesis of the Daleks]]". The Doctor is given an opportunity (an order, even) to prevent or seriously alter the creation of the Daleks. The only obvious downside is that at that point the Daleks hadn't done anything wrong (yet), and so he'd be committing genocide against a thus-far innocent race, who he knew would turn evil and try to wipe out entire species... [[spoiler: he didn't, merely delaying their development for a while, for which [[TimeyWimeyBall causality]] is thankful]]
** And according to {{fanon}}, enabling Davros to survive when his creations turned on him. When he was revived later in the original series, he eventually plunged the Daleks into civil war and undercut their threat to the universe for some time.
** The scandal surrounding Creator/JimmySavile turns "[[Recap/DoctorWho1985JFIGSAFixWithSontarans A Fix with Sontarans]]" into this for the Doctor and Tegan.

* ''Series/StargateSG1'' does it in the episode "2010" with Carter's husband wondering if the other timeline will really be better and what happens to them if the plan succeeds. Carter then bluntly tells him that "they" won't exist or exist but in a different way and that the new timeline cannot be worse than the absolutely certain destruction of humanity in less than 200 years. As we know, despite the new enemies appearing later on, she was entirely right.

* In the ''Series/{{Supernatural}}'' episode "The Song Remains the Same", the angel Anna goes back in time to kill John and Mary Winchester before Sam and Dean are born in order to prevent Sam and Dean from kickstarting the Apocalypse. Sam and Dean follow her to save John and Mary but take the opportunity to try to convince Mary to remain childless, as Sam and Dean are willing to cease to exist to stop the Apocalypse. This plan fails because the angel Michael, who is pro-Apocalypse, stops Anna and erases John and Mary's memories of the event.

* In the "ComicBook/AgeOfApocalypse" arc of MarvelComics; set in a changed present where Charles Xavier was killed in the past; Magneto and Rogue have a son. The Time Traveler Bishop wants to change things back. Magneto supports Bishop in this, but reminds him that if they succeed; his son will be gone forever. Presumably this also bothered some writers; who later wrote that this world continued to exist as an AlternateUniverse. (Btw, Jean Grey stopped the nukes in the end.)

* This is the main focus of ''Series/Continuum''. The protagonist is thrown back in time with a group of WellIntentionedExtremist s who wish to avert the dystopian future. She is faced with the dilemma of either trying to stop them and preserve her future at any cost, or trying to make the future a better place by preventing historical disasters and/or preventing murders. However, there are several added hurdles:

* This is the main focus''Series/Continuum''. The protagonist is thrown back in time with a group of WellIntentionedExtremists who wish to avert the dystopian future. She is faced with the dilemma of either trying to stop them and preserve her future at any cost, or trying to make the future a better place by preventing historical disasters and/or preventing murders. However, there are several added hurdles:

* Acknowledged and arguably justified in an episode of ''Series/{{Buffy|the Vampire Slayer}}'', involving not time travel but alternate realities. In the Season Three episode "The Wish", Cordelia wishes that Buffy had never come to Sunnydale, creating an alternate reality in which the town is overrun by vampires. Alt-Giles figures out how to reverse the effect, but at the last second, the demon responsible for it tries to stop him, asking why he thinks the alternate (original) universe is any better than the one he knows. Giles' response? "Because it has to be."

** Done beautifully in the episode "The Fires of Pompeii". The Doctor is saddled with the choice of not setting off Vesuvius, thereby saving Pompeii, or sending those people to their deaths in order to keep history intact [[spoiler:and to keep the Pyroviles from conquering Earth. Finally, with support from Donna, he sets off the volcano.]]
** Comes up again later in "The Waters of Mars;" only this time, [[spoiler:The Doctor changes history by choosing to intervene.]]

** The scandal surrounding Jimmy Savile turns "[[Recap/DoctorWho1985JFIGSAFixWithSontarans A Fix with Sontarans]]" into this for the Doctor and Tegan.

* Discussed and Averted in ''VisualNovel/VirtuesLastReward. [[spoiler:Although the goal of the AB project is to prevent the release of the Radical-6 virus, the timelines in which Sigma and Phi failed to do so still exist. Phi talks to you about it briefly as part of the Multi-World Interpretation, and Tenmyouji and Quark talk about it during the Golden Ending, and some ethical implications thereof.]]

* Aversion: Not TimeTravel, but worth commenting on; an AssPull justification that Marche of ''FinalFantasyTacticsAdvance'' gives regarding changing Ivalice back into [[UpTheRealRabbitHole "The Real World"]] is that surely the MagicalLand Ivalice will continue to exist as AnotherDimension after he destroys it.