Crossover ( episode ) An accident inside the wormhole sends Kira and Bashir into the " mirror universe " , where Klingons , Cardassians , and Bajorans rule over their Human slaves . Summary . Teaser . As Major Kira and Doctor Bashir make their way back to Deep Space 9 , Kira asks Bashir to take control of the runabout , as she has a headache and would like to meditate . Bashir mentions that he once had the opportunity to study with a rhythmic breathing expert named Isam Helewa , but Kira seems less than interested . When he mentions that he would like to learn any Bajoran techniques , Kira tells him that Bajorans usually just sit quietly . There is a brief pause as Kira meditates before Bashir begins breathing spastically . She looks up , irritated , and asks him what he is doing . He explains that he is using a technique called Bellows Breath meant to increase one ' s energy flow . In an attempt to change the subject , Kira suggests that they listen to some music . An undaunted Bashir asks what type the Major prefers , but unfortunately her musical knowledge is limited to Bajoran composers . He immediately tells the computer to play a selection by Tor Jolan , one of Bajor ' s greatest composers , much to Kira ' s surprise . She wonders how he knows of Tor and he explains that he has made a point to listen to Bajoran music since he was assigned to DS9 . They seem on the verge of finding a common ground when he starts comparing Tor to the great Boldaric masters of the previous century which seems to further annoy Kira . He remains as gung ho as ever , attempting to get to know Kira on a first - name basis . Bashir goes on to say that Nerys is one of the most interesting women he has ever met and he is glad they are putting their past conflicts behind them . Kira sarcastically adds that they are making room for new ones . Laughing , Bashir relates that he and Chief O ' Brien were once at odds with one another , but now he claims they are " like this " as he crosses his fingers . He presses on , trying too hard as usual , and tries to get Kira to call him Julian instead of Bashir . However , when he attempts to hit on her , she tells him to stick with Dax instead . This finally silences the doctor . As their runabout drops out of warp , the warp field does not collapse properly and they are engulfed in a white flash upon entering the wormhole . When they exit the Bajoran wormhole in the Alpha Quadrant , they are shocked to see the station is gone , instead orbit ing Bajor much as it did during the occupation . Before either of them can react , the runabout ' s sensor s detect a Klingon attack cruiser moving towards them . Two Klingon officers beam aboard the runabout and are shocked to see Kira . Apologizing profusely , they offer to escort her back to the station ; she simply nods , obviously confused . Upon arriving at , the two Klingons confer with a Cardassian officer named . Bashir and Kira board the station , where they are confused to see Garak and even more confused to see another . . . dressed entirely in black . Act One . Bashir politely asks where they are and Garak informs him that they are aboard , the center of authority in the Bajoran sector for something simply referred to as " the Alliance . " Kira observes that she and Bashir took a wrong turn at the wormhole , suggesting they return to their runabout . However , the other Kira , whom the Klingons and Garak address as " Intendant , " seems to have other plans . Bashir attempts to intervene , only to be vociferously chastised as a " " for his tone of voice . The Intendant believes she has an idea of who their visitors are , and if she is right , she tells Kira she cannot let them go . Dismissively , she orders one of the Klingons to put Bashir to work . Garak and the remaining Klingon escort Kira as they follow the Intendant out the airlock area and onto an identical version of the Promenade . Large flags display what appears to be a winged version of the Cardassian emblem enveloping the Klingon emblem , and below the flags , exhausted Humans carry large pieces of machinery in service to the Klingons and Cardassians . A Klingon officer named Telok informs the Intendant that a Terran has been discovered attempting to stow away aboard a freighter and brings the man to her . Approaching the Terran , the Intendant takes on a compassionate tone , asking his designation ; she is dismayed to hear he is a Theta and observes how long and hard he had worked to earn this designation . Her tone changes to business as she tells Garak to send the Terran to the mine s . Garak wants to execute the Terran to make an example of the man , but the Intendant claims Garak has made a career out of setting examples . He presses the issue , pointing out that two other Terrans have been caught trying to escape and asking that he be allowed to conduct an interrogation at least . While the Intendant permits this , she warns Garak not to kill his prisoner . Elsewhere on the station , an ore processing section identical to the one on DS9 houses dozens of Humans , who perform the same slave - like role as their Bajoran counterparts once did in the " normal " universe . As Bashir is escorted to the processing area , warns that they need to upgrade one of the machines ' thorium containment cells or there will be an accident . The Klingon escorting Bashir brings him to Odo and informs Odo that Bashir does not know the rules . Odo asks Bashir for his designation . Bashir can only think of his name , which Odo interprets as a joke ; as a result , Odo brutally slaps him . Again , Odo asks for a designation , so Bashir informs Odo he does not have one ; Odo corrects him , adding " sir " to the end of the statement . A rhetorical response garners another slap . Bashir becomes visibly enraged as they talk , but it is apparent that Odo takes perverse pleasure in provoking him . Upon hearing that Bashir is a doctor , Odo sarcastically reminds him to scrub before he operates . Bashir is put to work but notices that O ' Brien has observed the exchange with great interest . Leading Kira and the guard escorting her to Ops , the Intendant passes several Alliance emblems before entering the office normally occupied by Benjamin Sisko . She sits and urges Kira to do the same , dismissing the guard , her eyes feasting on Kira like an excited child on Christmas . The Intendant reveals to Kira that almost a century ago , a Human named James T . Kirk accidentally traded places with his mirror universe Terran and drastically altered the course of history on this side . At the time of the switch , the Terran Empire was barbaric but strong . While in the mirror universe , Kirk met a Vulcan named and had what the Intendant calls a " profound influence " on him . Spock preached peaceful reforms after " our " Kirk left , rising to commander in chief of the Empire in the process of doing so ; however , once he had completed his reforms , the Empire was too weak to defend itself from the newly - formed Klingon - Cardassian Alliance . Kira wonders how fits into the picture . The Intendant explains that the planet had been occupied by the Terrans for decades when the Empire fell . Upon becoming free , it petitioned for entry into the Alliance and became " quite an influential member " in later years . Her story finished , the Intendant wonders if the other side is similar at all . Unfortunately , Kira informs the Intendant that her Bajor has not been so fortunate . The Intendant is eager to hear about life in Kira ' s universe , but Kira insists that she cannot stay . However , the Intendant does not know " how " to send her back , nor " could " she if she wanted to do so . The Alliance , upon seizing power , declared that any visitors from other universes must be killed immediately to prevent future incursions after the first crossover , but unlike Garak , she says she does not like using violence . Kira knows exactly what she means , and that she is looking for an excuse not to kill " our " Kira . Kira solicits the Intendant ' s help , as she feels a leader like the Intendant could teach her what she needs to know to bring about a stronger Bajor in her universe . " " My side once changed the course of your history " , " she says . " " Well , maybe your side can change mine " . " While the idea appeals to the Intendant , she says she will still have to kill Bashir . When Kira asks her not to , she says letting him live is too dangerous and the Klingons and Cardassians would not allow it ; however , Kira knows herself too well and points out that the Intendant does not give a damn what the Klingons or Cardassians think . " " Oh ! " " the Intendant croons . " " You know how to manipulate me ! " " She agrees to go along with Kira ' s idea and calls for a guard to find her some quarters . Act Two . The next day , Kira , who has essentially been given free rein , visits the ore processing center to find a now - filthy Bashir pushing a cart full of ore . Mirror Odo greets her at the door . Like his counterpart on the other side , he prides himself on his efficiency . He offers assistance should she need him to explain anything , and when she demurs , citing that she has worked in ore processing before , he laughs out loud . When Kira mentions the name Kirk to Bashir , he immediately realizes where they are , having read about the transporter accident at the Academy . He plans to befriend the mirror O ' Brien in the hope that this O ' Brien knows as much about transporters as theirs does ; meanwhile , Kira tries to find other help . Greeting Garak amicably , Quark attempts to act as if nothing is wrong . However , Garak informs him that he is under arrest for helping Terrans escape from Terok Nor . Quark claims he is a coward who does not stick his neck out for anyone , but the Terran whom Garak interrogated has said otherwise . Knowing what is about to happen , Quark pulls out a Cardassian phaser rifle and attempts to escape , only to be dragged away by the Klingons . " " I shall miss him " , " Garak observes . " " He always let me win at dabo . " " Shortly thereafter , and a group of Terrans enter , helping themselves to free drinks in Quark ' s absence , and Kira sees another potential window of opportunity . Meanwhile , the exhausted Terrans are allowed a lunch break . Bashir seizes this opportunity to introduce himself to the mirror O ' Brien . Handing what little food he has been given to one of the other workers , he makes his way over to where O ' Brien is fixing a panel of some sort . Hearing that the two of them are best friends in the other universe piques this O ' Brien ' s interest ; he wonders what he does on the other side . Bashir informs him that he is chief of operations of the station , giving him reason to pause his work and consider the possibilities . When Bashir describes the other details of his O ' Brien ' s life , mirror O ' Brien says his other half must have gotten the lucky draw of the two of them . Bashir switches subjects , asking how much O ' Brien knows about transporters . While he claims to be no expert , he adds that he knows as much as any Terran . " " I hope that will be enough " , " Bashir remarks , explaining about the transporter plan . O ' Brien finds the plan untenable and believes Bashir is lying to solicit his help . While Bashir insists that he is sincere , the spell that came over O ' Brien when he heard of his other half seems broken , as he goes back to work and tells Bashir he does not know him . Odo interrupts to announce that break time is over and that Sisko has requested O ' Brien ' s presence . O ' Brien protests that he must finish his repair work , but as usual , no one listens to him . Back in Quark ' s , Sisko and the other Terrans are enjoying themselves at the bar and he remarks that the Intendant called him all the way from the Fowla system just to see Kira . She observes that he and his friends do not act like typical Terrans . As he explains , the Intendant provides him with a ship in exchange for " duties . . . of a sort " that he collects from other vessels . While most Terrans are enslaved , he and his crew are allowed relative freedom because he amuses the Intendant . He observes that Kira must amuse her as well . O ' Brien enters the bar to ask what Sisko wanted , and seeing him seems to brighten Sisko ' s day . Referring to O ' Brien as " Smiley " despite O ' Brien ' s objection to the nickname , Sisko asks how he is being treated in an attempt to make small talk . He observes that Smiley does not like him , which O ' Brien reluctantly confirms , evoking a laugh from Sisko . He states that the fact that Smiley is not afraid to show this dislike is why he amuses Sisko . Getting to the point , Sisko tells O ' Brien that his impulse driver coil needs to be repaired . O ' Brien notes the problems in ore processing which he needs to fix first , but Sisko cannot be bothered with such things and orders him to fix the ship first . As the Intendant calls for Sisko and he leaves the bar , Kira realizes that she may not have any hope at all . Act Three . Kira enters the Intendant ' s quarters to find the Intendant in a bathtub with several Vulcan servants massaging and bathing her as Sisko sits on a couch facing the door . The Intendant wants to know if there is another Sisko on the other side , and on hearing there is , the idea of two of Sisko pleases her . As she speaks , Sisko gets up to check on his ship , obviously not amused , but the Intendant stops him to ask if she has hurt his feelings . Obediently , he replies , " " I never had any to hurt " , " and exits . Once Sisko is gone , the Intendant talks to Kira as the Vulcans help her out of the tub and dress her . She mentions that she has heard Kira is looking for a transporter , and Kira reminds the Intendant that she is looking for a way back home . However , had Kira come to the Intendant with her request , she would know that transporters were re - designed after the first crossover to prevent future accidents . That leaves the Intendant to wonder why Kira did not do so . As she approaches Kira , her voice betrays a combination of hurt and distrust . Kira reluctantly admits that she is afraid of the Intendant . " " I don ' t want your fear " , " the Intendant confides as she stands face - to - face with Kira , " " I want your love . If you can ' t love me , who can ? " " The door chime rings . Telok informs the Intendant that Garak has arrived with a prisoner . She tells them to come inside ; they drag Quark , who has visibly been beaten , with them . As Quark apologizes for what he has done , the Intendant kneels beside the Ferengi and comforts him , explaining that he helped the Terrans because he felt sorry for them . However , she reminds him that the Alliance needs the labor to process ore , for without the Terrans , nobody would perform such tasks . Rising to her feet , she tells Garak to give Quark a quick death and seems to all but forget about the incident as Quark is dragged away begging for mercy . Kira is aghast , but the Intendant , now in a happy mood , announces she plans to throw a party . " " What shall we wear ? " " she asks her pet . Kira enters her quarters carrying a lavender dress to find Garak waiting for her . " " Lovely " , " says the Cardassian of the garment . " " I do admire a well - tailored gown " . " He proceeds to explain that the Intendant will never let Kira return to " our " universe as she is clearly enamored with Kira . Describing how the Intendant talks about Kira constantly , Garak compares Kira to a Drathan puppy lig left on the Intendant ' s doorstep and hints at his true intentions as he makes a point of mentioning that the Intendant trusts Kira with her life . Kira points at the guard outside her door as evidence of how much the Intendant trusts her , but Garak reveals that he arranged the guard , not the Intendant . " " Oh , she trusts you , as much as she trusts anyone . So who better to betray her ? " " he suggests . Garak ' s plan is that the Intendant will be " gone " in the morning and Kira will take her place . Shortly thereafter , he explains that Kira will retire to Bajor and he will take her place , at which point he will become the Intendant and Kira and Bashir will be sent home . He leaves Kira to ponder the idea and adds that , should she refuse , he has arranged for Bashir rather than the Intendant to be gone . Act Four . Hurriedly entering the ore processing center , Kira warns Bashir that the two of them must escape tonight . She does not have time to explain the web of lies and treachery , but she tells him to be careful because he might be in danger . Regardless of where they go from there , she insists that they must find a way to the runabout . She tells him that there will not be much warning if an opportunity presents itself so he should be prepared . On the Promenade , Kira finds Sisko half asleep , his eyes closed , leaning against a pillar . She claims to have valuable information that she is willing to trade , and he finds amusement in the idea that Kira has already " gone into business for herself . " When she tells him she wants her runabout or a way off the station , he laughs . " " She ' ll have my head . . . or something else " , " he says of the Intendant ' s reaction to such a plan . Kira dispenses with the negotiations and announces that Garak is planning to kill the Intendant . However , Garak has been doing so since he first arrived on the station . She reveals the plot in hope that it will convince him she is serious , but he laughs and observes that the plan is more creative than Garak normally gets . Frustrated , Kira wants to know why Sisko does not seem to care about the fact that he and his fellow Terrans are slaves ; he counters by arguing that he has made the best of a bad life for himself . Disgusted , Kira accuses Sisko of being no less a victim than anyone else noting that out of everyone she has met in this universe the only person who had a shred of decency was , of all people , Quark ; as she leaves , her words seem to weigh heavily on his conscience . Kira attends the Intendant ' s party in Quark ' s that night wearing the purple dress and Garak greets her charmingly . Telok brags to his fellow Klingons about his time in service to the , commenting on the unpredictable nature of and , when one of Sisko ' s crewmembers accidentally bumps into him . He punches the Terran dismissively , adding , " " Stupid Terran pig ! " " The Terran pulls out a knife and rises to his feet , but does so with restrained anger as he knows he is not an equal . At seeing that the Terran is willing to challenge him , Telok nods approvingly , ready for a fight . However , when Sisko shakes his head , the Terran puts the knife away . " " What ' s wrong , Terran ? " " Telok taunts . " " Lost your nerve ? " " Telok spits in the Terran ' s face and the man almost loses control , but another shake of the head from Sisko prompts him to restrain himself . Visibly disgusted , Telok orders the Terran to get out of his sight , and as the man does so , Sisko takes his place threateningly . However , the room shifts its attention as the Intendant enters . The guests cheer as the Intendant enters followed by her Vulcan servants and the musician asks what her pleasure is . She tells him to play something bright in a happy mood and joins the festivities as Kira observes her , deep in thought . Meanwhile , Bashir sits exhausted in ore processing in front of a pile of rocks . Odo approaches him from behind and kicks him , noting that Bashir is not accustomed to the workload and , as such , has much to learn . " " It ' s a shame this is going to be your last night on the job " , " he adds , with a hint of sadistic pleasure . His taunting is interrupted when , just as O ' Brien warned , the thorium containment field on one of the machines short - circuits . The Terran workers scatter as Odo contacts engineering , and Bashir uses this opportunity to steal a phaser from one of the Bajoran deputies . Still facing the deputy , he begins to back out the doorway following the panicked workers . Odo spots Bashir and reaches for his own phaser , but Bashir shoots the Changeling , causing him to explode , and splattering goo everywhere . Not taking the time to gawk , Bashir leaves immediately . Act Five . Telok and some other soldiers can be heard in the distance as Bashir runs through one of the corridors and enters a conduit . A pair of Klingons runs by , oblivious to his location . He crawls a short way before he finds O ' Brien attending a panel on the wall . However , when he solicits O ' Brien ' s help , O ' Brien claims not to see him and goes about sealing the thorium leak . Bashir realizes it is futile and remarks that he thought O ' Brien was a decent man , which O ' Brien insists he is . O ' Brien is worried that the Alliance will find and kill him if he helps Bashir , but Bashir points out that O ' Brien , as well as every other Terran , is already dead . He begins to enter another conduit , but O ' Brien points out that the runabout pads are through another conduit , asking if there is room on the ship for him . The two of them emerge in another corridor only to find the Klingons have cut them off . Interrupting the party , Telok brings O ' Brien and Bashir and informs the Intendant of what has transpired ; she immediately looks at Kira furiously . She declares that Odo ' s death is her fault for keeping Bashir alive in the first place and laments Odo ' s death . Garak and the others observe closely as she proclaims that Garak will use Bashir as his " example , " and kill him slowly in public view for all Terrans to see . When Kira attempts to speak , the Intendant threatens to have Kira join him . She then turns her attention back to O ' Brien . As he has been a perfect worker for years , she wonders what got into him , and he tells her that hearing about life on the other side and himself being chief of operations made him realize that , whatever the other side is like , there has to be something better than life as a Terran . " " Not for you , Mr . O ' Brien " , " the Intendant informs him . " " Oh , he ' s going to be taking you with him – just not exactly where you thought he would be taking you " . " With a nod from the Intendant , Garak begins to lead Bashir and O ' Brien out of Quark ' s , but taking Garak ' s gun from its holster , Sisko intervenes , inspired by O ' Brien ' s words . The Intendant does not believe what she sees and asks Sisko if he has lost his mind . He quietly replies , " " No , I didn ' t lose it . I just . . . changed it . " " By this time , " our " Kira and Sisko ' s crewmen have taken the cue and are all armed . They slowly exit the bar before Sisko shoots the panel above the door , locking it shut . As he does so , the Intendant is near tears ; for all the disparity between them , she had true feelings for Sisko . Kira warns Sisko as he escorts her and Bashir to the runabout pad that the Intendant will track him down wherever he goes . Bashir suggests that he and his crew come with them , but Sisko assures them he can stay ahead of the law . " " Maybe we ' ll stir up some things on " this " side " , " he adds with a grin . On hearing this , O ' Brien changes his mind about leaving and joins Sisko ' s crew , as Sisko says he can always use a good tinkerer and putterer . Kira thanks Sisko before she and Bashir board the runabout . Disengaging the docking clamp s , Bashir and Kira take the runabout straight to impulse and depart Terok Nor as quickly as possible . As they head for the wormhole , Bashir reports that the runabout still has a plasma injector leak from the warp core , which Kira is counting on to return them home . They mimic the conditions of their original entry into the wormhole that brought them to the mirror universe , but a Klingon cruiser heads straight toward them , trying to keep them from leaving and nearly destroying the runabout . However , as the Klingons on this side know nothing of the wormhole , Bashir and Kira are able to maneuver toward it and enter . They are inside the wormhole when one of the runabout ' s systems short - circuits and there is another brilliant flash of light . In Ops aboard Deep Space 9 , Commander Benjamin Sisko emerges from his office and asks if the crew has found anything . Odo stands next to Dax as she reports that a search vessel picked up traces of the runabout ' s warp signature and indications of a plasma leak , but no ship . There is an alert from the computer , and O ' Brien announces it is them , although their deflector grid is damaged . Sisko tells Dax to hail the runabout and with a mixture of annoyance and concern , asks where they have been . " " Through the looking glass " , " Kira responds . Memorable quotes . " " Bartender ! " " " " He ' s just been arrested . " " " " Arrested ? What a damn shame . Who wants a drink on the house ? " " " " I ' m Kira Nerys . " " " That makes two of us . " " " Wouldn ' t that be " something " , Benjamin ? Two of you at my side ! " " " " I need to check my ship . " " " " Benjamin . Did I hurt your feelings ? " " " " I never had any to hurt , Intendant . " " " " Smiley ! " " " " Miles , Mr . Sisko . " " " " I don ' t like the name Miles . That ' s why I named you ' Smiley ' ! " " " " What do you care about Terrans ' freedom ? " " " " I care about " freedom " ! What I don ' t understand is why you " don ' t " care . Why the only one I have met on this station who seemed to give a damn was a Ferengi toad named Quark ! " " " " On this side , Terran workers do not speak to their superiors as you do . They certainly do not murder them ! He was the only one of his kind , the man you killed . Do you realize that ? He ' s irreplaceable ! No one ran that operation as efficiently as he did . No one kept order among the workers as he did . This is my reward for treating you Terrans with the least bit of respect ! Very well . I can learn from my mistakes . You want to set an example , Garak ? Use him ! Set an example for all Terrans ! Let him die slowly in public view on the Promenade ! Let his pleads for mercy echo through the corridors for all Terrans to hear ! ! " " " " This man is a doctor where he comes from . And there ' s an O ' Brien there , just like me . . . Except he ' s some kind of high - up chief of operations . And they ' re Terrans . Can you believe that ? Maybe it ' s a fairy tale he made up , but it started me thinking how each of us might have turned out , had history been just a little different . I wanted him to take me with him because , whatever it ' s like where he ' s from , it ' s gotta be better than this . There ' s got to be " something " better than this . " " " " We ' ve got ships from here to New Bajor out looking for you . Where have you been ? " " " " Through the Looking - Glass , Commander . But it ' s good to be back . " " Links and references . References . 0413 Theta ; Alpha Quadrant ; arrest ; Bajor ; Bajor ( mirror ) ; Bajoran ; Bajoran music ; Bajoran sector ; Bajoran wormhole ; bath tub ; barbarian ; Bellows Breath ; ; Boldaric ; Cardassian ; chief of operations ; college ; commander in chief ; composer ; dabo ; Deep Space 9 ; deflector grid ; disruptor rifle ; dizziness ; docking clamp ; Drathan puppy lig ; driver coil ; Earth ( mirror ) ; electro - plasma ; emergency stabilization control ; euphemism ; fairy tale ; Fowla system ; Ferengi ; flags and banners ; Gamma Quadrant ; ; Intendant ; Isam Helewa ; joke ; jumja tea ; ; ; kiss ; Klingon ; Klingon - Cardassian Alliance ; Klingon cruiser ; ; latinum ; long range sensor ; ; medicine ; meditation ; mines ; mirror universe ; mirror universe cultures ; mirror universe history ; New Bajor ; ; ; nap ; Ops ; ore processing center ; " pagh " ; parallel universe ; Promenade ; plasma injector ; Promenade ; Quark ' s ; Quark ' s ( mirror ) ; rhythmic breathing ; Rules of Obedience ; runabout ; Smiley ; soul ; ; spoon ; Starfleet ; Starfleet ( mirror ) ; Starfleet Academy ; supervisor ; ; Terran Empire ; Terran Rebellion ; Terok Nor ( mirror ) ; theta ( classification ) ; thorium ; thorium containment cell ; thruster ; toad ; Tor Jolan ; transporter accident ; ; Vulcan , warp field ; wormhole