History Recap / StarTrekS1E28TheCityOnTheEdgeOfForever

* TragicTimeTraveler: Dr. [=McCoy=] accidentally travels back in time to The '30s and manages to make the entire Federation become Ret-Gone. Kirk follows him with an away team and falls in love with a local woman named Edith Keeler, whose life Bones saved from a car accident. Unfortunately, it turns out this was a linchpin event that led to Nazi Germany winning World War II, because in the altered timeline she led a pacifist movement that kept the United States out of the war. The crew are forced to let her die to restore the timeline.

* TragicTimeTraveler: Dr. McCoy accidentally travels back in time to The '30s and manages to make the entire Federation become Ret-Gone. Kirk follows him with an away team and falls in love with a local woman named Edith Keeler, whose life Bones saved from a car accident. Unfortunately, it turns out this was a linchpin event that led to Nazi Germany winning World War II, because in the altered timeline she led a pacifist movement that kept the United States out of the war. The crew are forced to let her die to restore the timeline.

* InformedAttribute: For a ''Guardian of Forever'', it certainly doesn't do anything to stop a drug-addled crazy man from runing into the past and screwing with human history, the sort of thing a ''Guardian'' would be expected to prevent. Maybe 'Watcher' would have been more accurate to call it, seeing as it's a gateway that does its job, which doesn't include changes to the timeline (by it anyway).

* InformedAttribute: For a ''Guardian of Forever'', he certainly doesn't do anything to stop a drug-addled crazy man run into the past and screw with human history, the sort of thing a ''Guardian'' would be expected to prevent. Maybe 'Watcher' would have been more accurate to call 'him', seeing as he's a gateway who does his job, which doesn't include changes to the timeline (by it anyway).

** It's insanely unlikely that one outspoken pacifist could have single-handed sabotaged the Allied cause so significantly. Regardless of her motives, Edith would have almost certainly been seen as just another isolationist like Lindbergh. After all, the America First Committee did attract its share of genuine pacifists. And how exactly is she supposed to have succeeded where Lindbergh failed? We know she gets popular in the alternate timeline, but does her fame really eclipse that of Lucky Lindy?
** Changing history by making USA enter war late or not enter it at all would have many, many consequences which could possibly help the Nazis win World War II[[note]] And it should be noted that "Hitler wins the war" does not necessarily mean "Hitler conquers the world," though even a negotiated nazi victory would undoubtedly still be a very unpleasant geopolitical condition[[/note]]. Britain could be deprived of vital supplies and eventually forced to surrender. Russians could be unable to launch their great 1943 counteroffensive without all those means of transport and communication they got from Americans, and without the US strategic bombing campaign sapping its frontline strength, the Luftwaffe could've been a ''much'' bigger problem on the Eastern Front. Japan could build its empire in Asia unopposed. However, the screenwriters decided to pick one factor on which USA not partaking in war would have little to no impact whatsoever. Contrary to popular belief, the Nazi nuclear program was not nearly as advanced as the Manhattan Project, and it was [[https://en.wikipedia.org/wiki/Norwegian_heavy_water_sabotage successfully derailed in 1943]] thanks to actions of British Special Operations Executive, without any American involvement.
** Spock claims that with V2 ballistic rockets at their disposal, Nazis would be able to deliver nuclear payload anywhere they want. In reality, V2's maximum range was only 380 kilometers -- not even close enough to endanger USA or other distant allied powers. In addition, the V-2 rocket had a payload that weighed about 2,000 pounds. That was pretty much the limit that it could carry, so it never would have been able to even get off the launch pad with a primitive nuclear weapon based on 1940's technology. Fat Man and Little Boy, the atomic bombs dropped on Japan, each weighed just over 10,000 pounds. The Germans ''did'' have some more advanced delivery systems, such as the long-range ''Amerikabomber'' project, the V-5 multistage ballistic missile, and the ''Silbervogel'' orbital bomber (whose concept was eventually developed into the Space Shuttle), but only the first of these ever made it into the prototype phase.
* TheBadGuyWins: In the alternate timeline, Adolf Hitler conquers the world. And as if the stakes needed to be any higher, a side effect of Enterprise's Xindi arc is that also in this timeline there is no Jonathan Archer to stop the Sphere Builders.

* BlatantLies: Kirk tries to pass of Spock's ear shape as being a result from surgery after an accident with a mechanical rice picker while in Asia. Naturally, no one buys it.

* DownerEnding: Kirk goes after [=McCoy=] after the latter briefly goes mad on an experimental drug. The two end up traveling back in time, where Kirk meets Edith Keeler. They hit it off and it seems like he's finally found true love, but it's then revealed that she's doomed to die in a traffic accident. Kirk thinks about saving her life—only to learn that if she survives, she'll start a pacifist group that will delay the United States's entry into World War II, which will in turn allow Hitler to develop atomic technology and defeat the Allied Powers. Despite truly loving the woman, Kirk is forced to watch, knowing full well what's about to happen, as she starts crossing the street where she'll be struck. This episode ends with the only profanity uttered in the original series: Kirk's famous line "Let's get the hell out of here."

* BigApplesauce: Of all the places on Earth to which Bones (and later Kirk and Spock) could travel, he happens to choose New York City.

* GodwinsLawOfTimeTravel: To quote Spock in David Morgan-Mar's treatment of this episode in ''Webcomic/PlanetOfHats'', "It's the First Law of Time Travel. [...] Time travel: ergo, Hitler." Bones going back to 1930 and preventing Edith Keeler's death causes the Nazis to win World War II.

-->'''Guardian of Forever:''' Time has resumed its shape. All is as it was before. Many such journeys are possible. Let me be your gateway.
-->'''Uhura:''' Captain, the Enterprise is up there. They're asking if we want to beam up.
-->'''Kirk:''' [[ScrewThisImOuttaHere Let's get the hell out of here.]]

* BeenThereShapedHistory: Kirk, Spock, and Bones were ''[[StableTimeLoop already]]'' there in 1930. If they had not have been, Edith would not have been distractedly crossing the street at that exact moment...and would have not been struck by the truck.

* NiceJobBreakingItHero: This would have been how history remembered Edith Keeler, had she been allowed to live. She was a saintly Depression-era social worker who, had she not been killed in a hit-and-run, would go on to lead a nationwide peace movement that would keep the U.S. out of World War II for several years beyond that of the original timeline — allowing the Nazis more time to develop nuclear weapons, ultimately win the war, and presumably cause TheEndOfTheWorldAsWeKnowIt. Nice job — wait, never mind.

* PopCulturalOsmosisFailure: Bones is well-aware of what movies are, but hasn't a clue who Clark Gable is.

* UnwittingInstigatorOfDoom: Both [=McCoy=] and Edith Keeler.

** McCoy changes the past such that Germany won WWII, drastically altering Earth's history such that there's no Federation or Starfleet and thus no Enterprise waiting in orbit. This is far more plausible than the way these stories are widely played, where a Nazi Federation arose and somehow there's still an Enterprise in orbit but it's run by Nazis.

* Kirk and Spock travel back in time to Depression-era New York in order to avert a disastrous event that changed history, but they don't know what it is. Fortunately for them, the information is stored on their tricorders. Their tricorders are damaged and Spock works to fix them, but he quickly finds it almost impossible. No matter how smart Spock is, the tricorder is centuries ahead of the most cutting-edge technology available at the time, and he's been trained to use highly advanced tools in a time where getting a pound of pure gold or platinum for your amateur electronics project is no simple matter - he compares it to working with "stone knives and bearskins". He's reduced to working with consumer-grade electrical goods such as lightbulbs and radio sets, and can only get a few seconds of functionality out of the tricorder after days of work. Also, in order to buy those materials he and Kirk need to work menial odd jobs and live in a homeless shelter, and in order to fit in they steal clothes off a clothesline... where they are promptly confronted by a police officer.
* McCoy changes the past such that Germany won WWII, drastically altering Earth's history such that there's no Federation or Starfleet and thus no Enterprise waiting in orbit. This is far more plausible than the way these stories are widely played, where a Nazi Federation arose and somehow there's still an Enterprise in orbit but it's run by Nazis.

* SurprisinglyRealisticOutcome: Kirk and Spock travel back in time to Depression-era New York in order to avert a disastrous event that changed history, but they don't know what it is. Fortunately for them, the information is stored on their tricorders. Their tricorders are damaged and Spock works to fix them, but he quickly finds it almost impossible. No matter how smart Spock is, the tricorder is centuries ahead of the most cutting-edge technology available at the time, and he's been trained to use highly advanced tools in a time where getting a pound of pure gold or platinum for your amateur electronics project is no simple matter - he compares it to working with "stone knives and bearskins". He's reduced to working with consumer-grade electrical goods such as lightbulbs and radio sets, and can only get a few seconds of functionality out of the tricorder after days of work. Also, in order to buy those materials he and Kirk need to work menial odd jobs and live in a homeless shelter, and in order to fit in they steal clothes off a clothesline... where they are promptly confronted by a police officer.

* IDidWhatIHadToDo: James Blish wrote the short-story adaptations for many of the episodes. When he wrote this one, it's subtly hinted that Spock was going to kill Edith himself, it that was what it took to restore the timeline. If the actual episode, Spock does -very gently- chide Kirk for catching Edith when she was falling down a flight of stairs, reminding him that he will have to ''think'', not ''act'', when the moment comes.

* TheStoryThatNeverWas: The episode ends with this trope {{implied|trope}}.When [=McCoy=] gets drugged and falls through a mysterious portal through time, his changes to the timeline cause the ''Enterprise'' to disappear from the present. Kirk and Spock follow [=McCoy=] into the portal, arriving in UsefulNotes/NewYorkCity in TheThirties. They meet the peace activist Edith Keeler, and soon realize that she's the change in the timeline. [=McCoy=] saved her (or will soon save her) from an early death, and her activism will delay the USA's entry into UsefulNotes/WorldWarII just long enough to lead to a BadFuture where UsefulNotes/NaziGermany wins. So Kirk prevents [=McCoy=] from rescuing Keeler--erasing [=McCoy's=] involvement in the past and restoring the timeline to normal.

** Changing history by making USA enter war late or not enter it at all would have many, many consequences which could possibly help the Nazis win World War II. Britain could be deprived of vital supplies and eventually forced to surrender. Russians could be unable to launch their great 1943 counteroffensive without all those means of transport and communication they got from Americans. Japan could build its empire in Asia unopposed. However, the screenwriters decided to pick one factor on which USA not partaking in war would have little to no impact whatsoever. Contrary to popular belief, the Nazi nuclear program was not nearly as advanced as the Manhattan Project, and it was [[https://en.wikipedia.org/wiki/Norwegian_heavy_water_sabotage successfully derailed in 1943]] thanks to actions of British Special Operations Executive, without any American involvement.
** Spock claims that with V2 ballistic rockets at their disposal, Nazis would be able to deliver nuclear payload anywhere they want. In reality, V2's maximum range was only 380 kilometers -- not even close enough to endanger USA or other distant allied powers. In addition, the V-2 rocket had a payload that weighed about 2,000 pounds. That was pretty much the limit that it could carry, so it never would have been able to even get off the launch pad with a primitive nuclear weapon based on 1940's technology. Fat Man and Little Boy, the atomic bombs dropped on Japan, each weighed just over 10,000 pounds.

* RealityEnsues: Kirk and Spock travel back in time to Depression-era New York in order to avert a disastrous event that changed history, but they don't know what it is. Fortunately for them, the information is stored on their tricorders. Their tricorders are damaged and Spock works to fix them, but he quickly finds it almost impossible. No matter how smart Spock is, the tricorder is centuries ahead of the most cutting-edge technology available at the time, and he's been trained to use highly advanced tools in a time where getting a pound of pure gold or platinum for your amateur electronics project is no simple matter - he compares it to working with "stone knives and bearskins". He's reduced to working with consumer-grade electrical goods such as lightbulbs and radio sets, and can only get a few seconds of functionality out of the tricorder after days of work. Also, in order to buy those materials he and Kirk need to work menial odd jobs and live in a homeless shelter, and in order to fit in they steal clothes off a clothesline... where they are promptly confronted by a police officer.

* TheGlomp: Bones gets one of these from Kirk near the end when the latter and Spock are overjoyed to finally find him, but the happy celebrations are cut short because Edith Keeler is hit by a car seconds later.

* HeroicBSOD: Kirk ends the episode in one of these.

* {{Leitmotif}}: "Goodnight, Sweetheart" is ''their'' song.

* BornInTheWrongCentury: Edith's ideals came off as preachy in her time, but were accepted in Kirk's times

** Changing history by making USA enter war late or not enter it at all would have many, many consequences which could possibly help the Nazis win World War II. Britain could be deprived of vital supplies and eventually forced to surrender. Russians could be unable to launch their great 1943 counteroffensive without all those means of transport and communication they got from Americans. Japan could build its empire in Asia unopposed. However, the screenwriters decided to pick one factor on which USA not partaking in war would have little to no impact whatsoever. Contrary to popular belief, Nazi nuclear program was not nearly as advanced as the Manhattan Project, and it was [[https://en.wikipedia.org/wiki/Norwegian_heavy_water_sabotage successfully derailed in 1943]] thanks to actions of British Special Operations Executive, without any American involvement.

** Changing history by making USA enter war late or not enter it at all would have many, many consequences which could possibly help Nazis win World War II. Britain could be deprived of vital supplies and eventually forced to surrender. Russians could be unable to launch their great 1943 counteroffensive without all those means of transport and communication they got from Americans. Japan could build its empire in Asia unopposed. However, the screenwriters decided to pick one factor on which USA not partaking in war would have little to no impact whatsoever. Contrary to popular belief, Nazi nuclear program was not nearly as advanced as the Manhattan Project, and it was [[https://en.wikipedia.org/wiki/Norwegian_heavy_water_sabotage successfully derailed in 1943]] thanks to actions of British Special Operations Executive, without any American involvement.

** It's insanely unlikely that one outspoken non-interventionist could have single-handed sabotaged the Allied cause so significantly. Regardless of her motives, Edith would have almost certainly been seen as just another isolationist like Lindbergh. And how exactly is she supposed to have succeeded where Lindbergh failed? We know she gets popular in the alternate timeline, but does her fame really eclipse that of Lucky Lindy?

** After Spock first finds the newspaper footage of both Edith's obituary and her apparent future meeting with President Roosevelt, he points out to Kirk that they don't yet know whether [=McCoy=] will kill Edith, or prevent her death. The next scene has [=McCoy=] appearing in the street and chasing a terrified man while shouting "I won't kill you! It's they who do the killing!"