Mirror universe The " mirror universe " is an informal name for a parallel universe widely recorded as first being visited by James T . Kirk and several officers from the in 2267 . This parallel universe coexists with the prime universe in the same space , but on another dimensional plane . The mirror universe was so named because most places , ships , and people who existed in the regular universe also existed there , although often as the antithesis of their characteristics in the prime universe , with numerous good aspects evil and vice versa , thus " mirror " - like . ( ; ; ) As of 2257 , the existence of each universe was classified by the opposite universe ' s dominant power . ( ) History . Terran Empire . In the mirror universe , much of known history is dominated by the Terran Empire . It is not clear when the Empire began . Captain once stated that the Empire had existed for " centuries " as of 2155 . Archer did not mention how many centuries , but by his statement , the Empire can be traced back to at least 1955 , suggesting that it was a Terran political unit before it became an interstellar empire . ( ) First Contact between Vulcan s and the Terran Empire took place in 2063 , as it did in the prime universe . A long history of nations warring with each other , the stronger overcoming the weaker , led the people of Earth to believe that conquest was the only means of surviving in the universe . Peace was only a ruse used to determine an enemy ' s weaknesses and to enable the one offering peace a chance to conquer from within . So , when the Vulcans landed and made their peaceful introduction , shot the first Vulcan to step onto soil instead of welcoming them with open arms ( as in the prime universe ) , and the Terrans , interpreting the landing as prelude to an invasion , raided the Vulcan ship . The shotgun used by Zefram Cochrane later came into the possession of , who wondered what would have happened had Cochrane not " turned the tables " on the Vulcans ' " invasion force . " With advanced Vulcan technology at their disposal , the Terran Empire expanded and conquered other races , including the Vulcans , Andorian s , Tellarite s , Orion s , and Denobulan s . In 2155 , the , under the command of Captain Maximilian Forrest , was the flagship of the Terran Empire ' s . In January of that year , Commander Jonathan Archer mutinied against Forrest in order to take the ship into Tholian space to capture the , which had traveled through a spatial interphase from the year 2268 in the prime universe . While the mutiny was ultimately unsuccessful , Captain Forrest had no choice but to continue the mission , since the ship ' s helm had been locked on auto - pilot . The " Enterprise " was later destroyed by Tholian ships , but not before Archer was able to take control of the " Defiant " . ( ) Archer tried to use the " Defiant " in a grab for power , intending to replace the emperor , but was betrayed by , who declared herself empress . ( ) Sometime between 2155 and 2267 , the symbol of the Empire appears to have been altered . The earlier symbol closely resembles that of the United Earth government , depicting all of Earth ' s continents , though replacing a laurel of peace with an aggressive sword . However , by 2267 , the symbol , while remaining essentially the same , depicted only the continents of Earth ' s western hemisphere . By the mid - 23rd century , the Terran Empire was the dominant power in the Alpha Quadrant . The Empire , ruled by Emperor , had at some point in the past century conquered ; some Klingons joined Vulcans , Andorians and Tellarites in rebellion against the Terrans ' rule . In the 2250s , Captain attempted a coup against Emperor Georgiou . She sent her adoptive daughter , Captain , to apprehend Lorca , but instead Burnham joined Lorca ' s insurrection . Burnham was subsequently believed to have been killed when her shuttlecraft was destroyed ; Lorca was publicly blamed for her death . Eventually , Lorca was betrayed by scientist . When Lorca was attempting to recruit allies on Priors World , the Emperor caught up with him . He attempted to transport to his ship , the , but the transporter beam was caught in an ion storm and Lorca was transported to the prime universe . ( ) Lorca successfully impersonated his prime universe counterpart and in 2256 became captain of the . He also recruited the Michael Burnham of the prime universe , though he hid his true origins and motivations from her . Late that year or early in 2257 , Lorca used " Discoverys " displacement - activated spore hub drive to return to the mirror universe . He convinced Burnham to impersonate her mirror universe counterpart and bring him as her prisoner aboard Burnham ' s ship , the . As he had planned , when Emperor Georgiou heard that Burnham was alive , she summoned her to bring Lorca to her flagship , the . Lorca escaped from an agonizer booth on the " Charon " and rescued several of his followers who were also being imprisoned and tortured there . With their help , he took control of the " Charon " , but he and his surviving followers were defeated by Emperor Georgiou and Michael Burnham . Lorca was apparently killed , and Burnham and the Emperor were beamed off of the " Charon " before it was destroyed by " Discovery " . ( ) Fearing that people would purposely attempt to cross over in order to bring back a lost loved one , the prime universe ' s Starfleet classified the very existence of the mirror universe in 2257 . ( ) In 2267 , four Starfleet officers ( Captain James T . Kirk , Lieutenant Uhura , Lieutenant Commander Montgomery Scott , and Doctor Leonard McCoy ) from the USS " Enterprise " were exchanged with those same officers from the in the mirror universe because of transporter interference from an ion storm , they discovered a brutal regime , almost dictator ial in its command structure . Advancement through assassination was commonplace . During the encounter , Captain Kirk convinced the counterpart of his first officer , , that the Empire could not sustain itself . Indeed , Spock predicted that in its current form , the Empire had 240 years before total collapse . ( ) Shortly thereafter , Spock rose to become leader of the Terran Empire , proposing a series of reform s designed to make the Empire more secure and less dictatorial in nature . These included a significant disarmament program . Unfortunately , once these reforms were complete , the Empire was unable to defend itself against the equally aggressive and powerful forces surrounding it . The Klingon - Cardassian Alliance overran the Empire , enslaving s and Vulcans , and freeing several worlds that still remained under Terran occupation , including . ( ) Klingon - Cardassian Alliance . With the fall of the Terran Empire , the Klingon - Cardassian Alliance became the dominant power in the Alpha Quadrant . Bajor , which before had been enslaved by the Terrans , soon joined the Alliance . The command post and ore processing facility was constructed in orbit . Also during this time , the forces of the mirror universe began implementing safeguards to prevent another crossover event . Transporter design was altered to prevent inter - dimensional travel , requiring the creation of devices specifically for that purpose , including the multidimensional transporter . In the event of another crossover , those involved would be killed to prevent further interference . ( ) By 2370 , Terok Nor was commanded by Intendant , with as her second - in - command . It was at this point in time that contact with the prime universe again took place . A runabout from station Deep Space 9 entered the mirror universe following an incident in the Bajoran wormhole . Kira Nerys and Julian Bashir were captured by forces from Terok Nor , and interrogated by the intendant . Bashir was sent to work in the ore processing plant , where he befriended . After instigating a series of incidents aboard the station , including the death of during a slave uprising , Kira and Bashir convinced privateer to rebel against the Alliance and help them to escape back to the prime universe . ( ) A year later , Smiley crossed over to the Federation ' s universe and impersonated his counterpart long enough to capture the prime Sisko and bring him back to the mirror universe , where he convinced Sisko to impersonate the leader of the Terran Rebellion . The mirror Sisko had been killed in a skirmish with Alliance ships , and the rebels needed the other Sisko to win over , Sisko ' s wife , who in the mirror universe was a scientist working for the Alliance . Jennifer had been developing a transpectral sensor array , which would have allowed the Alliance to locate rebel hideouts in the Badlands . Sisko convinced his wife ' s mirror counterpart to defect to the side of the rebels . ( ) While in the Federation ' s universe , Smiley downloaded information from Deep Space 9 ' s computers , including the plans for the . In 2372 , the rebels constructed their own version of the " Defiant " , but had trouble getting it to function properly . Jennifer lured Sisko back into the mirror universe to help , though Kira Nerys killed her a short time thereafter . By this time , the rebellion had grown in strength , culminating in the capture of Terok Nor , which became a rebel base of operations . ( ) In 2374 , Intendant Kira sent a thief , , to the prime universe to steal one of the Bajoran orb s , believing it would permit Kira to unite Bajor under her rule . The attempt failed , and Bareil returned to the mirror universe without the orb . ( ) In 2375 , Grand Nagus Zek , the leader of the Ferengi Alliance in the prime universe , used the multidimensional transporter to travel to the mirror universe along with his Hupyrian manservant , Maihar ' du , hoping to open up business opportunities , but they were captured and held hostage by the Alliance . Kira made arrangements with , the regent of the Alliance , to obtain the prime universe ' s version of the Klingon cloaking device in exchange for Zek ' s return . She sent , a Trill mercenary and Kira ' s lover , to the prime side to give Quark the ransom demand . Quark and his brother Rom stole the cloaking device from Klingon General Martok ' s ship and delivered it to Ezri , but decided at the last minute that they couldn ' t trust her to keep her side of the deal . Quark and Rom accompanied her to the mirror universe , where all three were captured by the Terran rebels , who planned to keep the cloaking device , until Ezri ' s companion freed them , delivering them to Regent Worf . Aboard Worf ' s flagship , Quark and Rom were imprisoned along with Zek upon discovering Kira ' s plan , only to be later rescued by Ezri as revenge against Kira for killing Brunt . Ezri ended up joining the rebel cause . Quark , Rom , Zek , and Maihar ' du were allowed to return to the primary universe for having aided the rebels ' defeat of Worf , a major victory for the rebellion . During the escape from Worf ' s ship , Garak was killed . When last seen , the rebels ' march towards victory showed no apparent signs of slowing . ( ) Appendices . Background information . Origins . Jerome Bixby was inspired to conceptually originate the mirror universe , as a parallel universe , after writing a short story called " One Way Street " , which also features a parallel universe . " " Having written ' One Way Street ' , I thought ' OK , parallel universe ! " " he exclaimed . Allowing the show ' s regular cast to play alternate versions of the main characters was one motive Bixby had for inventing the mirror universe . " " As I was searching for ideas , I knew that they loved to use their cast in unusual ways on " Star Trek " . Instead of just throwing the cast up against a group of bad guys , or space monsters eating planets , they got a kick out of putting the cast into unusual versions of themselves , in an evil persona . " " ( " " , issue # 164 , p . 48 ) Indeed , Bixby also said , " " The universe I created was a very savage counterpart , virtually a pirate ship , into which I could transpose a landing party . " " ( " Captains ' Logs Supplemental - The Unauthorized Guide to the New Trek Voyages " , p . 74 ) However , Bixby ’ s original version of didn ' t actually depict the parallel universe as " a very savage counterpart " , with only subtle differences from the prime universe , such as the fact the " Enterprise " therein was manned by a benevolent crew . Harlan Ellison had proposed including a savage alternate universe in his original take on and the parallel universe setting in the story that became " Mirror , Mirror " initially worried Robert Justman that it might be too similar to the antimatter universe from . ( " " ) While the story gradually began to develop into " Mirror , Mirror " , the imagined universe evolved too . In a revised story outline ( submitted on ) , the universe contained a version of Rigel IV and a war which the duplicate Federation , including the alternate " Enterprise " , was losing against a race called the Tharn , to the point where surrender of the Federation was proclaimed as imminently necessary . Under orders from Admiral McNulty , Kirk took the " Enterprise " to rendezvous with elements of the Tharn fleet and submitted the ship to them . As Kirk soon realized , however , the Tharn vessels didn ' t have shields to withstand a phaser blast and the Federation had no knowledge of phaser technology . Next , ten Tharn ships followed the " Enterprise " , still acting under orders from McNulty , to the nearest starbase , which was Starbase One . During transit , the existence of the other universe , and the fact Kirk had originated there , was discovered by Mirror Spock and Mirror Scott . The crew of the Mirror " Enterprise " finally managed to create a phaser weapon , with Kirk ' s help , and used it to defeat the Tharn , before Kirk was returned to his own reality . ( " " ) Some aspects of the mirror universe were subsequently influenced by comments from Script Consultant D . C . Fontana . For example , she suggested distinguishing the parallel universe from the prime one by doing " something optically or photographically . " Thus , the first on - screen view from the mirror universe , depicting the ISS " Enterprise " and the Halkan homeworld , is a flipped rendition of identical footage from the prime universe . ( " " ) The mirror universe was drastically changed when Gene Roddenberry submitted a rewrite of the story treatment on . He had found a way to make a parallel universe comprehensible , also changing the name Tharn to that of an individual and renaming the race as the Halkans . Roddenberry had started to think of the mirror universe as analogous to a country under the political control of a fascist military junta . Expressing how he thought of the alternate reality , Roddenberry mused to Gene L . Coon , " " Life is valueless , full of fear and terror , and never exploits the full potential of most of the citizens . " " ( " " ) A few wording alterations still needed to be made . After Jerome Bixby proceeded from Gene Roddenberry ' s blueprint by turning in a first draft script for " Mirror , Mirror " on , some clarifications regarding the mirror universe were required . In a memo , Roddenberry told Gene Coon , " " Desperately needed are scenes where we , in effect , sit down and say , ' This is where we are ; this is what we ' ve seen ; what does it add up to ? ' [ . . . ] For example , on Page 11 , Kirk says , ' We ' ve got two theories : massive change in our normal setting , or we ' re someplace else . ' I had to read this several times to understand what he meant . " " Following a second draft of the teleplay ( submitted by Bixby in ) , NBC Broadcast Standards Department objected to the character of referring to the mirror universe as " the damned universe , " advising that either the word " damned " be deleted or that the phrase be changed to " the universe of the damned . " ( " " ) In retrospect , referring to the murderous activities rife in the alternate universe , Marlena Moreau actress Barbara Luna half - jokingly commented , " " We take that sort of thing lightly in the Mirror Universe . " " ( " " , issue # 235 , p . 80 ) First reappearance . Since " Mirror , Mirror " became a favorite episode with fans of , it seemed only natural for the mirror universe to reappear in a later incarnation of " Star Trek " . ( " " , p . 143 ) As early as , David Gerrold jokingly reported that the mirror universe played a part in the only sequel to a TOS episode that had been suggested so far , in which the " Enterprise " returned to the parallel universe . ( ' , issue # 119 , p . 21 ) The notion of revisiting the mirror universe on TNG was actually pitched to the series many times , ever since it began . ( " Captains ' Logs Supplemental - The Unauthorized Guide to the New Trek Voyages " , p . 74 ) One undeveloped mirror universe episode was even written for and submitted to TNG by Jerome Bixby . ( ' , issue # 164 , p . 45 ; " " , issue # 167 , p . 5 ) However , Michael Piller was uninterested in the idea of revisiting the mirror universe . ( " Captains ' Logs Supplemental - The Unauthorized Guide to the New Trek Voyages " , p . 74 ) Explained Brannon Braga , " " We were a little frightened at doing it , and doing it badly , and maybe never really figured out what the " Next Generation " take would have been on it . " " The writing staff of talked , for a while , about returning to the mirror universe , prior to setting any such plans in motion . ( " " , p . 143 ) " " We were talking about the idea of doing a sort of a mirror universe , " " commented Robert Hewitt Wolfe , " " and so , we started to imagine what that mirror universe would be like , if we put our people into it . " " ( " Section 31 : Hidden File 03 " , DS9 Season 2 DVD special features ) The parallel universe reappeared in the DS9 episode because Michael Piller was intrigued by the possibility of finding out how the reality had been altered since its introduction . " " I couldn ' t get away from the fact that it would be interesting to know what happened after ' Mirror , Mirror ' finished , " " he said . Influenced by watching " Schindler ' s List " , Piller was fascinated by the what - if aspect of the grim alternate realm . ( " Captains ' Logs Supplemental - The Unauthorized Guide to the New Trek Voyages " , p . 74 ) Wolfe remarked , " " So , that was kinda the idea , was what would the mirror universe be like , a hundred years later ? Well , it might not be a very nice place . " " Changing the mirror universe in this way , pointing out that Kirk had been naive to try to simply improve the parallel universe without any unexpected consequences , was " fun " for Wolfe . ( " Section 31 : Hidden File 03 " , DS9 Season 2 DVD special features ) Portraying the mirror universe in " Crossover " involved production requirements that were extremely demanding . ( " Captains ' Logs Supplemental - The Unauthorized Guide to the New Trek Voyages " , p . 74 ) The production staff had the responsibility of convincing the DS9 audience that they were once again viewing events in the mirror universe . ( " " , p . 143 ) Director David Livingston relished the challenge , since " Crossover " was the first installment to revisit the location . " " That was fun to sort of be on the ground floor of creating this other world , " " he commented . ( " Section 31 : Hidden File 08 " , DS9 Season 2 DVD special features ) Outlining some of the extra needs , Livingston said , " " We had more prosthesis makeup because the [ space ] station < nowiki > [ < / nowiki > < nowiki > ] < / nowiki > is inhabited by Klingons , Cardassians and Bajorans , and the humans are basically slaves so they ' re wearing different costumes . " " Other requirements involved altering the space station itself . ( " Captains ' Logs Supplemental - The Unauthorized Guide to the New Trek Voyages " , p . 75 ) Production Designer Herman Zimmerman noted , " " It was more lighting and costuming than anything physical that we needed to do . " " The alternate universe was deliberately depicted as " weird " , such as by using skewed camera angles . " " It looked unusual and immediately told the viewer he was in another world , " " stated Livingston , who devised the idea . ( " " , pp . 143 - 144 ) Thus , the notion of making the installment ' s imagery very strong and dramatic set a visual tone for the mirror universe , helping differentiate it from the prime reality . " " Stylistically , I tried to carry that same theme through the episode , so that it had a really strong contrast to what happens on our side of the world , or our side of the universe or reality . " " ( " Section 31 : Hidden File 08 " , DS9 Season 2 DVD special features ) As for clothing the main characters in both " Mirror , Mirror " and " Crossover " , many of the costumes were variations on the ones normally worn by the lead actors in their " Star Trek " roles . ( " " , p . 144 ) The performances of the characters obviously also changed . " " You suddenly get to flip your character . It was part of the of " Star Trek " , " " related Kira actress Nana Visitor , who was delighted not only to appear in the mirror universe of " Crossover " but also to introduce the character of the Intendant . ( ) Although Bashir actor Alexander Siddig was one of three members of DS9 ' s main cast who didn ' t appear as their usual character ' s mirror duplicate in " Crossover " ( Terry Farrell and Cirroc Lofton being the others ) , he nonetheless thoroughly enjoyed watching the altered performances of all his cast mates . ( " " , p . 144 ; ) When the mirror universe started being revisited on " Star Trek : Deep Space Nine " , Jerome Bixby was very upset that he received no acknowledgement , in " Crossover " , for the reuse of the concept . " " They did refer to the visit by Captain Kirk and his landing party , and I perked up when they mentioned that , " " he admitted . Bixby was so disappointed about not receiving on - screen credit for the recycling of what he felt was an idea he had originated that he consulted the Writer ' s Guild of America , whose policy was that – if a writer created an original character that was later reused – the writer was entitled to a royalty of some money . " " It ' s arguable , " " Bixby explained , " " that the Mirror universe itself might be termed a ' character ' [ . . . ] I ' m not sure that the ' Mirror , Mirror ' spin - offs will [ result in financial compensation ] unless the Mirror universe itself can be deemed a character . That was mentioned in passing by the guy at the guild . " " ( " Captains ' Logs Supplemental - The Unauthorized Guide to the New Trek Voyages " , p . 74 ) Later appearances . DS9 ' s second visit to " the other side " was proposed by Robert Hewitt Wolfe to Ira Steven Behr and they proceeded to write the episode , , together . ( " Captains ' Logs Supplemental - The Unauthorized Guide to the New Trek Voyages " , p . 94 ) The writers were faced with a choice of how difficult ( or easy ) to make accessing the mirror universe . " " Every time we wanted to do a mirror universe show , " " said Behr , " " we had to come up with tech [ to explain how they got there ] . It came down to , did you want to spend half an act finding ways , or did you want to get in there and have fun ? So , we made it easier to get in . But at least our [ prime universe ] people didn ' t come up with the way to do it . The mirror universe people did . " " Nonetheless , Wolfe added , " " I would say that it " was " probably extremely difficult to do , but [ off screen ] . " " ( " " , p . 230 ) Although Ronald D . Moore hardly had anything to do with " Through the Looking Glass " , he highly valued the revisit to the mirror universe , later remarking , " " I want to know more of what happened . " " ( " Captains ' Logs Supplemental - The Unauthorized Guide to the New Trek Voyages " , p . 94 ) However , some viewers seemed concerned that accessing the mirror universe in " Through the Looking Glass " appeared to be too easy . ( " " , p . 230 ) The use of the " alternate dimension " in " Through the Looking Glass " allowed for a cameo appearance by Tim Russ as . " " You ' re dealing with a basic physics concept , theoretical physics – the concept of an alternate universe – and I thought it was wonderful , " " Russ commented . ( " Captains ' Logs Supplemental - The Unauthorized Guide to the New Trek Voyages " , p . 94 ) Nana Visitor also enjoyed how the mirror universe was depicted in " Through the Looking Glass " . " " It was fun to watch everyone else work and see them as this other side of themselves , " " she said . ( ) The mirror universe setting of " Through the Looking Glass " meant the episode took an unusually long time to produce . " " These shows have to be shot in a certain style because it ' s an alternate universe , " " observed David Livingston . " " Even though " Deep Space Nine " is already moody and dark , this universe has a certain sinewy look to it , and [ Director of Photography ] Jonathan [ West ] said , ' If you want it then I have to take the time to do it . ' We all kind of bit the bullet , and it went over tremendously . It [ the extra time needed to portray the mirror universe ] was not a surprise to me . It might have been a surprise to some people , but I had been there . " " ( " Captains ' Logs Supplemental - The Unauthorized Guide to the New Trek Voyages " , p . 95 ) Almost everyone working on " Star Trek : Deep Space Nine " enjoyed the " Crossover " episodes , which is how they generally referred to installments set in the mirror universe . Writers , actors , and directors alike relished the opportunities to take the characters in a direction which could be completely different from their norm . ( " " , p . 229 ) To the DS9 writers , in fact , a visit to the mirror universe was like a vacation . ( " " , p . 329 ) Michael Piller noted , " " The ' Mirror , Mirror ' arc episodes [ of DS9 ] were all great fun . " " ( ) Hans Beimler enthused , " " The alternate universe . . . [ is ] a great , fun playground . We get to paint with big brushes . The bad guys are so villainous and the good guys are so good . " " ( ) He elaborated , " " I think the fun thing about the alternate universe , [ is ] you get to use the " Star Trek " characters , but you can make up rules as you go along . " " Laughing , Beimler continued , " " It ' s an alternate universe , but so much of it is blank , that you can really do what you ' ve been wanting to do in our universe and can ' t do . " " Ira Behr commented , " " Let ' s face it , the alternate universe is such a wacky idea , and I don ' t care what anyone says [ . . . ] Though we tried to play it with a straight face , at first , in " Deep Space Nine " , as time went on it just became tougher for us not to see it as what it was , which was kind of a rather flakey alternative to what we had been doing [ . . . ] To really enjoy the alternate universe episodes , you just have to let go , you have to relax your sphincter a little bit and not be so anal about it , and just try to have some fun . " " Behr also described the mirror universe as " something that we were able to exploit pretty successfully for a number of years . " ( " Cinefantastique " , Vol . 32 , Nos . 4 / 5 , pp . 72 & 73 ) Ron Moore considered the mirror universe as " just [ a ] wildly fun " setting , commenting , " " It ' s a cool universe , and it ' s kind of fun to go over there and see the world turned inside out [ . . . ] If anything , you want to see more and more of that world [ . . . ] It loosens up the characters a little bit [ . . . ] The logic of this parallel existence , where all our people look exactly the same but play other characters , is tenuous at best . Rick [ Berman ] has always kind of stumbled on it . He always stumbles on it , then he always likes the episode . I think it ' s how we all feel . It seems like a place to go and relax and have a good time . " " René Echevarria pointed out , " " When you see those characters , you see how much fun the actors have getting to play these shadow versions of themselves . " " ( " Captains ' Logs Supplemental - The Unauthorized Guide to the New Trek Voyages " , pp . 118 & 94 ) David Livingston remarked , " " [ One ] thing that I like about doing those kinds of episodes [ . . . ] [ is ] the cast members get to play other characters and they get a big kick out of it . You know , it ' s a hoot for them to break out of something that they have to normally play the same every week [ . . . ] And they chew the scenery and relish in it . It ' s fun to watch them do that . " " ( " Section 31 : Hidden File 08 " , DS9 Season 2 DVD special features ) Director James L . Conway agreed , " " It ' s great to have these actors be able to free themselves up and play completely different people who are semibasically the same . " " ( " " , p . 330 ) One exception to those who praised the mirror universe was Garak actor Andrew Robinson , since he didn ' t like the mirror Garak . " " I never liked those alternate universe shows , " " Robinson complained . ( " " , p . 645 ) On the other hand , he admitted , " " I know these stories are popular , though . " " ( " " , issue # 237 , p . 74 ) There was obviously a temptation to go as far afield as possible with differentiating the mirror universe characters from their prime universe counterparts , though there were seemingly limits to this . For example , mirror universe characters that apparently remained much the same as their prime universe counterparts include Spock , Tuvok , and Jadzia Dax . Alternatively , some characters ( such as ) could be vastly different in the mirror universe to how they were otherwise portrayed , according to Winrich Kolbe , who directed " Through the Looking Glass " . Because the mirror universe episodes of DS9 had a high body count of familiar characters who were eliminated , the writers occasionally worried about running out of characters to populate the alternate realm . " " It ' s a brutal universe , " " acknowledged Robert Hewitt Wolfe , laughing . ( " " , pp . 229 & 230 ) Although the mirror universe inspired the DS9 writing staff to have fun , there were some in - house rules the writers had to follow when depicting the alternate universe . " " We can ' t just go over there and interfere with their culture just because we can , " " said Hans Beimler . " " That ' s not a good enough reason . Ira ' s very specific about this . He wants the crossover shows [ . . . ] to have what he calls ' bond , ' which means there must be a reason to do them . The crossover universe [ . . . ] [ is ] a swashbuckling kind of place . But we can ' t go there just because we ' re in a swashbuckling mood . We must go there for a [ specific ] reason . " " ( " " , p . 331 ) While directing DS9 Season 4 installment , James Conway bore in mind the prevalent eroticism of the mirror universe . " " That ' s what the mirror universe is about , " " he remarked . " " It ' s dark and it ' s sexy , so you can ' t be afraid of that in those shows because you ' d miss opportunities . There ' s no subtlety over there . " " Hans Beimler concurred , " " The alternate universe is a sexually charged place , and who does what to whom is a matter of great interest to us . " " ( " " , p . 331 ) At about the end of DS9 ' s fourth season , the show ' s writing staff thought it likely that the mirror universe would appear again . Ira Steven Behr said , " " It ' s something we ' ll probably do [ . . . ] But you have to find a worthwhile story . There ' s also a big push to have them come to us . . . We ' ll see . " " René Echevarria believed it was reasonable to expect there might be another " crossover " episode , commenting , " " This is a piece of the franchise we want to do every year , but we ' re always looking for an in that is more than just playing great games [ . . . ] People always say they want those guys to come to our universe , but the idea of them impersonating one of our people , unfortunately , is an angle we sort of cover with the changeling s . So what does that really give you ? That ' s why we keep going there . " " Ron Moore concluded , " " I can see still going over there [ as a possibility ] . " " ( " Captains ' Logs Supplemental - The Unauthorized Guide to the New Trek Voyages " , p . 118 ) After freelance writer Michael Taylor tried to tackle an ultimately during the show ' s sixth season , he and the series ' writing staff began speaking about the possibility of doing another mirror universe episode . ( " " , p . 509 ) " " I wasn ' t crazy about going back to the alternate universe , " " Ira Behr conceded . ( " Cinefantastique " , Vol . 30 , No . 9 / 10 , p . 44 ) The DS9 producers consequently decided to stick with the plan of setting their fourth episode about the mirror universe , which was entitled , in the prime universe throughout , meanwhile bringing mirror universe characters there , such as Intendant Kira and the mirror - Bareil . ( " " , p . 509 ) As " Star Trek : The Next Generation " had completely bypassed the mirror universe , LeVar Burton – who starred as Geordi La Forge on TNG and directed numerous DS9 episodes – wasn ' t exposed to the mirror universe until he was called upon to direct " Resurrection " . The producers ' decision to set the entire installment in the prime universe meant Burton had little difficulty with directing the episode . The only element of the mirror universe he may have experienced trouble with – namely , filming scenes of the two Kiras interacting – was actually no problem for him , as Burton had already shot two Rikers in the TNG offering . ( " " , p . 509 ) Shortly before the start of DS9 ' s seventh and final season , Ira Behr began to plan another mirror universe episode . Timing was one of the main factors that motivated the return of the alternate universe in seventh season entry . ( " " , pp . 330 & 644 ) Hans Beimler remembered , " " We knew we had to do an alternate universe story , that it would be the last time we did an alternate universe story , so we wanted to make it a really great send - up . " " Behr added , " " We all felt the need , with a small n , to revisit the alternate universe one last time . " " ( " Cinefantastique " , Vol . 32 , Nos . 4 / 5 , p . 72 ) Additionally , Behr proclaimed , " " The mirror universe was due for a Ferengi show . " " ( " " , p . 644 ) Regarding how the mirror universe was somewhat comedically depicted in " The Emperor ' s New Cloak " , Behr stated , " " We finally got to question the whole lunatic idea of the mirror universe . " " ( " " , p . 643 ) This was done via the Ferengi character of Rom , who comes to the realization that the alternate universe " just doesn ' t make any sense . " Slightly more than a year after having directed " Resurrection " , LeVar Burton again returned to the subject of the mirror universe by directing " The Emperor ' s New Cloak " . However , he didn ' t see the entire scope of " Deep Space Nine " s mirror characterizations until he started working on the episode . These performances pleased Ezri Tigan actress Nicole de Boer , who noted , " " I liked seeing everybody else ' s take on the mirror characters . " " ( " " , p . 644 ) She elaborated , " " That was so much fun [ . . . ] I had never seen the mirror universe episodes before , so I didn ' t really know what to expect . I thought everybody was so great [ . . . ] We just all have so much fun with it , being bigger , and campy . " " ( " Cinefantastique " , Vol . 32 , Nos . 4 / 5 , p . 46 ) Armin Shimerman referred to " The Emperor ' s New Cloak " as " the one last acknowledgement of the mirror universe people . " ( " Cinefantastique " , Vol . 32 , Nos . 4 / 5 , p . 36 ) Ira Behr commented , " " I thought all in all it was a doff of the hat , and a little bow , and a wink to [ . . . ] the alternate universe . " " Hans Beimler concurred , " " I think it was a nice way to end the last alternate universe [ episode ] , at least the last one we ' ll do . " " ( " Cinefantastique " , Vol . 32 , Nos . 4 / 5 , p . 73 ) Following his work on " The Emperor ' s New Cloak " , Hans Beimler hypothesized that the mirror universe might appear on . " " I ' m sure " Voyager " will steal our thunder , and go in there , " " Beimler contemplated . ( " Cinefantastique " , Vol . 32 , Nos . 4 / 5 , p . 73 ) His prediction turned out to be an incorrect one , as the alternate universe never appeared on VOY . However , Robert Duncan McNeill did once refer to the event horizon of a specific type - four quantum singularity , which appears in , as a " mirror universe . " ( " " , issue # 213 , p . 38 ) Prequel developments . According to the writers and producers of in a panel discussion at the Grand Slam XIII convention , the concept of featuring the mirror universe in ENT Season 4 had a long gestation period . " " We had talked about doing a mirror universe episode ever since we got into Season Four , " " recalled Manny Coto . In fact , Brannon Braga , who worked as co - creator and Executive Producer on ENT , even initially considered that an alternate timeline which had been introduced in the season finale of the previous season , , might be " the beginnings of the Mirror Universe . " ( ) The mirror universe was intended to be featured in an ultimately undeveloped two - parter which was concocted in the hopes of enabling William Shatner to appear . It would have been revealed that a method of exiting the mirror universe was via the Tantalus field , as it didn ' t actually disintegrate but in fact relocated its victims – which had included " Tiberius " , the mirror universe from " Mirror , Mirror " ( as played by Shatner ) – to a penal colony in the prime universe . " " And so by that interesting , fun notion , you would have a world where all these Mirror Universe characters had been living , " " stated Manny Coto . Returning to the mirror universe was of paramount importance to Tiberius and thus , when arrived at the penal colony , he was excited by the prospect of it allowing him to journey back to that reality . Much to his chagrin , however , the mirror universe didn ' t exist yet . In this narrative , it would have been created by Tiberius himself , as an alternate timeline split off from the prime timeline following the events of the show . ( " Before Her Time : Decommissioning " Enterprise " , Part Two : Memorable Voyages " , ENT Season 4 Blu - ray special features ) Although negotiations between William Shatner and Paramount failed to reach an agreement , the concept of using the mirror universe as the major setting of a story still appealed to the ENT team of writer - producers . Another hurdle was a continuity issue caused by the fact that the visit to the mirror universe in " Mirror , Mirror " had clearly been its first contact with the prime universe . Manny Coto said , " " We started bandying about ideas , trying to figure out a way to get our characters into the mirror universe . " " Coto further explained , " " When we were playing with the idea we kept going back to the old ' okay , they ' re beaming over and they get transported there ' thing [ . . . ] I hit upon the idea that why don ' t we just do the story in the Mirror Universe ? Not a crossover , but the whole episode in there , and then it hit me that we could treat it like the whole episode sort of beamed over from the Mirror Universe , and that turned into a two - parter . " " ( " Cinefantastique " , Vol . 37 , No . 2 , p . 41 ) Speaking from the viewpoint of the mirror universe , he concluded , " " There ' s very little interaction with our regular universe . " " Essentially , the creative team wanted to deliver the message that we ' re " not in Kansas anymore . " ( " Information provided by Mike Sussman " ) The concept that the mirror universe existed at least as far back as when First Contact took place between Humans and Vulcans was thought up by Manny Coto . ( " Before Her Time : Decommissioning " Enterprise " , Part Two : Memorable Voyages " , ENT Season 4 Blu - ray special features ) Prior to writing the script for " In a Mirror , Darkly , Part I " , Mike Sussman did some further research on the mirror universe by reading the non - canon novel " Dark Mirror " . ( " Information provided by Mike Sussman " ) The use of the mirror universe as the only setting of the " In a Mirror , Darkly " two - parter meant that aliens ( such as the Gorn and Tholian species ) which were otherwise prohibited from appearing on " Star Trek : Enterprise " , without violating canon , could be depicted in the two - parter . Hence , Garfield Reeves - Stevens related , " " One of the great attractions that Manny had for why he wanted to do a Mirror episode was that there were very few continuity issues [ within it ] . " " ( " Cinefantastique " , Vol . 37 , No . 2 , p . 69 ) Coto himself rhetorically asked , " " The mirror universe , you know , gave us so much and an original " Star Trek " vehicle , so how can you go wrong ? " " ( " Before Her Time : Decommissioning " Enterprise " , Part Two : Memorable Voyages " , ENT Season 4 Blu - ray special features ) Returning to direct events in the mirror universe by helming " In a Mirror , Darkly , Part I " was enjoyable for James L . Conway , having directed DS9 : " Shattered Mirror " . Of the ENT mirror universe show , he reminisced , " " Taking the characters and flipping their personalities completely was a delight . " " ( " Before Her Time : Decommissioning " Enterprise " , Part Two : Memorable Voyages " , ENT Season 4 Blu - ray special features ) In a cut scene from " In a Mirror , Darkly , Part II " , Archer gives a motivational speech to the assembled crews of the former ISS " Enterprise " and the " Avenger " . Brannon Braga revealed – via his Twitter account – that , before the cancellation of " Star Trek : Enterprise " , there was even some talk about setting the entire fifth season in the mirror universe . When interviewed , he explained , " " We were going to continue on with the Mirror Universe , in a major way [ . . . ] Manny Coto [ . . . ] had some big plans for the Mirror Universe . " " Coto himself stated , " " The mirror universe was a way , kind of , to expand old mythology , or touch on mythology without breaking canon , and that was gonna be our way to explore fun avenues that we weren ' t able to explore in regular universe . " " ( " Before Her Time : Decommissioning " Enterprise " , Part Two : Memorable Voyages " , ENT Season 4 Blu - ray special features ) Coto ' s plans for season five included featuring the mirror universe in four or five interconnected episodes . ( " Before Her Time : Decommissioning " Enterprise " , Part Three : Final Approach " , ENT Season 4 Blu - ray special features ) In , Simon Pegg jokingly theorized that the origins of the mirror universe crew from " Mirror , Mirror " might actually turn out to be depicted with the evolution of the alternate reality crew of the from that universe , revealing that they are actually one and the same crew . Dating divergence . The credits sequence for the mirror universe " Star Trek : Enterprise " television series used footage of battles going back at least to the " Age of Sail " . The mirror noted that the " great works " of literature in both universes were roughly the same , except that their characters were " soft and weak " ( except for Shakespeare ) , pushing back the latest possible date for a divergence to the 16th century . In mirror - Archer ' s deleted speech from " In a Mirror , Darkly , Part II " , he invokes the favor of the " gods . " This , together with ' s statement about " being the woman of a Caesar " , in " Mirror , Mirror " , suggests that the Terran Imperial tradition extends at least back to ancient Rome . However , given the nature of the mirror universe , these statements should be taken with a grain of salt . Crossover characters . This is a list of individuals known to exist both in the prime reality and in the mirror universe . Apocrypha . The existence of a " point of divergence " from the traditional " Star Trek " universe has not been confirmed , though according to the novel " Fearful Symmetry " , the mirror universe is in fact a parallel quantum universe , as quantum signature scans used to match Worf with his in were also able to differentiate natives of the mirror universe from those of the prime reality . This suggests that even though the two universes were always separate , they shared a similar past up to some point in their history . According to the FASA role - playing games and " The Best of Trek " , the mirror universe diverges from the prime timeline around the Eugenics Wars , while DC Comics ' " The Mirror Universe Saga " comics speculate the Earth - Romulan War was the point of divergence , with Earth having lost that war , and then embarking on a policy of conquest after overthrowing the Romulans ( it is not known what kind of contact ' s Empire had with the Romulans ) . Still other works , the novels of William Shatner ' s " " ( co - written with Judith and Garfield Reeves - Stevens ) and the seem to indicate that time travel of the Borg to Zefram Cochrane ' s era might be responsible . This explanation would tie in with when the Vulcans first arrived and were killed by Cochrane . " Dark Mirror " , a Pocket TNG novel by Diane Duane , at first appears to place the mirror universe as parallel since the Eugenics Wars but Picard discovers that the ending of Shakespeare ' s " Merchant of Venice " is drastically different : Shylock is awarded , and accepts , the owed pound of flesh . On further investigation Picard finds that in the mirror universe kills old King Priam after the death of Hector when asked to return Hector ' s body for funeral rites , instead of showing one moment of Humanity . Picard thought that that moment in the original prime universe version as the one time in the poem when " " that terrible man showed mercy . . . but not here . " " Picard also discovered that Surak of Vulcan hadn ' t existed in that version of the mirror universe . This universe is inconsistent with the others in that it was written before the DS9 mirror episodes and references the Terran Empire as still being active in 2367 ( although in a conversation with the mirror Worf Picard confirms Kirk and mirror - Spock ' s belief that the Empire will soon collapse , encouraging Worf to prepare other slaves to be ready to fight back ) . Alternate mirror universes might however explain some of the costume and effects inconsistencies in the DS9 mirror episodes . For example in , Alliance ships were seen de - cloaking , and in the Alliance didn ' t have cloaking technology . The mirror universe is mentioned a few times in the " Deep Space Nine " book trilogy " " . During the second novel , it was revealed that Dukat , possessed by the Pah - wraiths , has taken over the mirror Terok Nor , where he is awaiting a final confrontation with Kai Weyoun . Also , General Martok crafted an invasion strategy that would have involved moving the entire Klingon fleet to the mirror universe . In the novel " The Soul Key " by Olivia Woods , it is revealed that the mirror staged his death . In addition , the Bajoran wormhole is discovered by the mirror version of Iliana Ghemor . The mirror universe made an appearance in " " , a video game released for PCs . " Voyager " , having been pulled into a starship scrapyard , encounters hostile Humans working with various aliens , including Malons , Klingons , and Hirogen . These Human " scavengers " are from the mirror universe and operate from a station made up of the remains of a mirror universe starship , among other things . The mirror universe also features prominently in " " , a video game released on PS2 and Xbox . It depicts an of the 2290s , and a crossover to the adventures of Captain Sulu on the ISS " Excelsior " . According to the novella " Age of the Empress " , World War II occurred in the mirror universe , with Japan as one as its participants . One of the results appears to have been a lessening of the power of Japan ' s emperor , as the Kyoto Imperial Palace was turned into a tourist attraction . A mirror universe of the alternate reality is introduced in issue fifteen of IDW Publishing ' s " " comic series . In this version of events , ' s incursion results in a timeline where the Terran Empire conquers the Klingons in 2258 , and recovers the " " from . Having destroyed the and proclaimed himself captain of the " new " Terran flagship , Kirk subsequently tracks down another anomaly similar to that which brought the " Narada " into their universe and discovers another version of " Spock Prime " , who recognizes this world as the mirror universe . Kirk subsequently attempts to use the red matter from the " Jellyfish " to destroy Vulcan , but this plan is prevented by the treachery of , who beamed to safety at the last minute . The two Spocks decide to remain on Vulcan to help their people , while Uhura departs as the new captain of the " Narada " . The mirror universe plays a role in " Star Trek Online " . It appears in in the mission " Jabberwocky " , in which the player must return the mirror version of the Orb of Possibilities to that universe , while braving attacks from both the Cardassian True Way and the reformed Terran Empire . Personnel from the mirror universe also appear in the mission " Lost and Found " , as well as the later missions " Temporal Reckoning " and " Ragnarok " .