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Series: Series/{{Star Trek The Original Series}}\\
Episode: Season 2, Episode 4\\
Title: "Mirror, Mirror"\\
Previous: The Changeling\\
Next: The Apple\\
Recapper: Insert Witty Name Here]


The ''USS Enterprise'' is in orbit of a planet ruled by [[PlanetOfHats the peaceful Halkans]]. A landing party consisting of [[TheKirk Captain Kirk]], [[TheMcCoy Doctor McCoy]], [[BridgeBunny Lieutenant Uhura]] [[AndZoidberg and Scotty]] are on the planet to convince the Halkans to allow the Federation mining rights. The inhabitants of the planet, however, are convinced that HumansAreTheRealMonsters, and despite Kirk's assertion that if the answer is "no" then they will simply be on their way without troubling the Halkans further, the aliens remain entirely unconvinced.

The landing party beam back to the ''Enterprise''. But [[TeleporterAccident it all goes horribly wrong]], and our heroes find themselves TrappedInAnotherWorld. In this AlternateUniverse there exists not a [[TheFederation peaceful confederation of planets]], but instead an EvilEmpire that slashes and burns its way across the galaxy. The first and most obvious change is that Spock has [[BeardOfEvil got a goatee beard]]; but there are other signs: nearly all the walls of the ''Enterprise'' are [[SigilSpam emblazoned with a logo of a sword through the planet Earth]], and there are also [[AgonyBeam agony booths]] around, used for punishing misbehaviour among the crew.

Finally finding a moment to take refuge alone, our four man crew [[HuddlePower attempt to figure out what happened]]. They reason that an ion storm around the planet distrupted the transporter and sent them to a MirrorUniverse by accident, swapping them with their own counterparts from this universe. They make a plan to return home, replicating the unique situation that brought them here. But until then they will need to [[FishOutOfWater try and blend in]] as best they can. As for the unsettling thought of what their counterparts are doing, it turns out that Spock back in their own dimension has it under control; their barbaric character was immediately obvious to him and he had them hauled to the brig right away.

In his quarters, Captain Kirk meets [[GirlOfTheWeek Marlena Moreau]], who introduces herself as "[[FetishFuel the Captain's woman"]]. He resists the temptation to [[BoldlyComing Boldly Come]], instead subtly pressing her for information. Moreau introduces Kirk to the real source of his evil counterpart's power: [[NewPowersAsThePlotDemands the Tantalus field]], a device which he stole from an alien planet, and which allows him to [[OneHitKill evaporate people]] [[BigRedButton at the touch of a button]]. Kirk, naturally, [[WhatDoesThisButtonDo resists the temptation]] [[DontTouchItYouIdiot to push it and see what happens]].

Our crew put their plan into action. While Lieutenant Uhura distracts Evil Sulu from his security monitoring board, Scotty shorts out the main phaser couplings and siphons power off to the transporter. Kirk, in the meantime, has to deal with an [[KlingonPromotion assassination attempt]] by Evil Chekov, and another possible attempt from Evil Spock. In the sickbay, a fight breaks out between the crew and Evil Sulu's gang of thugs. Marlena Moreau evens the odds by using the Tantalus field to [[UnPerson remove]] Evil Sulu's gang, and our crew triumph. But Evil Spock arrives on the scene. His curiosity about the crew's bizarre behaviour since returning from the surface has been piqued, and he performs a MindRape on the doctor to get the full story.

Moreau [[EscortMission guides Kirk to the transporter room]], but then performs a HeelFaceTurn, deciding that she would rather come back to the prime universe alongside Kirk. To this end she pulls a phaser on him and starts making demands. Captain Kirk WouldntHitAGirl, but thankfully he's not required to, because Lieutenant Uhura sneaks up behind Moreau and instigates a DesignatedGirlFight (which she wins). One further obstacle comes in the form of Evil Spock, who arrives on the scene alongside the crew...

... but he too has performed a HeelFaceTurn, and receives AnAesop from Captain Kirk:

--> '''Evil Spock''': You must return to your universe. I must have my captain back. I shall operate the transporter. [[RaceAgainstTheClock You have two minutes and ten seconds.]]
--> '''Kirk''': In that time [[AnAesop I have something to say]]. How long before the Halkan prediction of galactic revolt is realised?
--> '''Evil Spock''': Approximately two hundred and forty years.
--> '''Kirk''': The inevitable outcome?
--> '''Evil Spock''': The Empire shall be overthrown.
--> '''Kirk''': [[KirkSummation The illogic of waste, Mister Spock. The waste of lives, potential, resources, time. I submit to you that your Empire is illogical because it cannot endure. I submit that you are illogical to be a willing part of it.]]
--> '''Evil Spock''': You have one minute and twenty three seconds.
--> '''Kirk''': If [[GrowingTheBeard change is inevitable, predictable, beneficial]], doesn't logic demand that you be a part of it?
--> '''Evil Spock''': One man cannot summon the future.
--> '''Kirk''': But one man can change the present. Be TheCaptain of this Enterprise, Mister Spock. Find a logical reason for [[AdoptTheDog sparing the Halkans]] and make it stick. Push till it gives. You can defend yourself better than any man in the fleet.
--> '''Scotty''': Captain, get in the transporter!
--> '''Kirk''': What will it be? Past or future? [[GiveMeLibertyOrGiveMeDeath Tyranny or freedom]]? [[TheOnlyOne It's up to you]].
--> '''Evil Spock''': It is time.
--> '''Kirk''': In every revolution, there's [[MessianicArchetype one man with a vision]].
--> '''Evil Spock''': Captain Kirk, I shall consider it.\\


Evil Spock activates the transporter and sends them home. Back in the prime universe, Captain Kirk goes over the events they have experienced, and is then surprised to discover that a new Lieutenant named Marlena Moreau is among his crew. But he stops just short of telling her "AndYouWereThere".

!!Tropes
* AgonyBeam: Both the Agony Booth and the Agonizer are classic examples.
* BeardOfEvil: The TropeMaker and the TropeNamer. Ironically, Mirror Spock is just about the ''least'' evil person in the Mirror Universe.
* ContinuityNod: Captain Pike is mentioned, as Mirror Kirk killed him to get his job.
* ADayInTheLimelight: For Uhura, along with (Mirror) Sulu and Chekov. Not for nothing is this episode considered one of the show's finest ensemble pieces.
* DesignatedGirlFight: Uhura and Marlena. Doubles as a CurbStompBattle, as Uhura totally owns Marlena from the word "go".
* DisintegratorRay: The Tantalus Field.
* TheEmpire: The Terran Empire, in obvious contrast to TheFederation.
* EvilCannotComprehendGood: While the crew from our universe are able to blend in fairly successfully, the Mirror crew who were brought over to the Prime universe were immediately caught.
--> '''Spock:''' It was far easier for you as civilized man to act as barbarians, than for them as barbarians to act like civilized men.
* EvilTwin: All of the Mirror Universe versions of the ''Enterprise'' crew. The Halkans appear to be about the same, though their Mirror counterparts are more resigned to their fate.
* FanService: Of both [[MrFanservice male]] and [[MsFanservice female]] varieties. Most notable are Uhura and Marlena in their [[TheissTitillationTheory barely there]] uniforms, but '60s Shatner had some nice arms.
* GenreSavvy: The prime Spock quickly figures something is wrong with the newcomers.
* GoodScarsEvilScars: Mirror Sulu definitely has the 'evil' kind.
* HumansAreTheRealMonsters: In the Mirror Universe, anyway. Spock has his own take on that subject, of course.
-->'''Spock''': They were brutal, savage, unprincipled, uncivilized, treacherous...in every way, splendid examples of ''Homo Sapiens''; the very flower of humanity. I found them quite refreshing.
-->'''Kirk''' (DoubleTake): I'm not sure, but I think we've just been insulted.
-->'''[[TheMcCoy McCoy]]''': ''I'm'' sure.
* InconvenientHippocraticOath: Despite Kirk having had to knock Mirror Spock out when he risked interfering in their plan to return home, [=McCoy=] insists on saving him - which would pay off for them in the end.
* KirkSummation: Surprisingly, it actually ''works''.
* KlingonPromotion: Apparently the ''only'' way promotion happens in the Imperial Starfleet. Mirror Kirk himself was promoted by assassinating Mirror Captain Pike. Mirror Sulu and Mirror Chekov ''both'' attempt this maneuver in the episode itself, impressive considering it takes place over a few ''hours''!
* KnifeNut: All of the Imperial Starfleet officers carry them as standard weapons. Mirror Sulu seems especially fond of his.
* LargeHam: Most of the Mirror Universe inhabitants but in his brief appearance, Mirror Kirk takes the cake (surprise, surprise...)
* MirrorUniverse: Again, the TropeNamer, as well as the TropeCodifier.
** UnbuiltTrope: The Halkans in the Mirror Universe are just as adamantly neutral as in the prime universe -- an attitude that leads them to near-destruction.
* OhCrap: Mirror Sulu's reaction that Mirror Spock's has Vulcans in his crew who would avenge him should he "disappear".
** And speaking of "disappearing", when Mirror Marlena uses the Tantalus Field on Sulu's men during his attempt to get rid of both Kirk and Spock, and Mirror Sulu suddenly finds himself outnumbered four-to-one.
* PunishmentBox: The Agony Booth again.
* RewardedAsATraitorDeserves: When one of Mirror Chekov'a henchmen switches sides, he mentions that while Chekov promised him a promotion to chief, Kirk could make him an officer. Our Kirk approves, then belts him to remind him who's the top dog.
* SlouchOfVillainy: The normally uptight and well-disciplined Starfleet {{Redshirts}} are seen leaning against the turbolift entrance to the bridge.
* SmugSnake: Mirror Sulu. In every one of his scenes he's up to no good, and he doesn't even try to hide it.
* VillainsBlendInBetter: {{Inverted}}; see EvilCannotComprehendGood.
* YouCalledMeXItMustBeSerious: This is the only time in both the series and the original movies that Scotty calls Captain Kirk "Jim", when he begs him not to stay behind to operate the transporter.