Extreme Measures ( episode ) Bashir and O ' Brien lure a Section 31 agent to the station in a desperate search for the cure to the disease that is killing Odo . ( Part 7 of 9 ) Summary . Teaser . Doctor Julian Bashir treats Odo in the Deep Space 9 infirmary , still unable to make any significant progress in curing his sickness . He estimates Odo has one week , perhaps two , before dying . Odo persuades Kira to leave his bedside to accompany Damar back to Dominion space in order to help the Cardassian Resistance , for his sake as well as hers . Elim Garak reminds Kira that they need to leave quickly before the Dominion border patrols are changed . Odo appears to be in an advanced state of decomposition , yet this does nothing to dampen their love for one another . He knows how hard it was for Kira to watch Vedek Bareil die in this very sickbay , and doesn ' t want her to see him die either . He makes it a request from him , to not to have to see pain in Kira ' s face . She decides to go , making it easier on the man she still loves . Chief Miles O ' Brien informs Captain Sisko that Starfleet now has the Breen energy - dampening weapon Kira and the others were able to procure , and a defense is being worked on . When Captain Sisko inquires of Odo ' s prognosis , O ' Brien suggests that a medical cure is not the only option they have been pursuing , at which point Sisko demands to know the whole story . Doctor Bashir reluctantly discloses his belief that Odo ' s sickness is a virus created by Section 31 to wipe out all Changeling s , leaving Sisko shocked that people who call themselves Federation citizens are attempting to commit genocide . Bashir also says that he has transmitted a report to Starfleet Medical , " falsely " claiming to have found a cure for Odo ' s sickness , in order to lure a Section 31 operative to the station ; once captured , the agent would be interrogated to help point Bashir in the right direction of finding a cure . Sisko then asks why they didn ' t tell him . Bashir answer that if they told him , then he ' d alert Starfleet Command and Section 31 would cover up their tracks once they realize they were discovered . They also tell the Captain they plan on using Romulan mind probe s , which are illegal in the Federation . Sisko knows that what his officers are doing is not only illegal but also highly unethical , but since the two are being forced to play dirty in a dirty game , he has no choice but to allow them to continue . Act One . Later that evening , O ' Brien stumbles across Bashir throwing darts in a closed Quark ' s ; each man is restless and feeling down in the dumps . Bashir tells O ' Brien that he , after thinking over the conspiracy to infect the Founder s with the disease , has concluded that at least seventy - three people must have been involved in the plot ; a fact that leaves a very bitter taste in his mouth . The two friends each view Section 31 as an evil that ' s crawled its way into the heart of the Federation , and that it must be destroyed . Afterward , Bashir awakens in his quarters to find Section 31 operative Luther Sloan sitting comfortably in a chair overlooking Bashir ' s bed , as he normally appears , saying he has another assignment ; but this time , Bashir is ready for him . The doctor activates a containment field , trapping Sloan where he sits . Bashir tells Sloan that he needs the cure to the morphogenic virus ; Sloan is confused , he thought Bashir had already had it but he soon realizes he doesn ' t . Sloan is impressed , but indicates that turning him over to security won ' t do any good . Bashir tells Sloan that he is not interested in turning the latter over to security , then stuns Sloan unconscious with a phaser . Sloan awakens in sickbay , immobilized with a force field encompassing his body . Sloan asks O ' Brien about his family , implying that if he dies , Section 31 will harm them . Yet Bashir doesn ' t believe him and tells Miles to not to listen to him . Bashir deduces that Sloan must have known the cure in order to find it in Julian ' s lab and destroy it . Bashir and O ' Brien prepare to use the Romulan mind probes on Sloan , who , for once , appears lost for a backup plan . He resorts to pleading with Bashir , saying he is genuinely sorry Odo has to die , but he cannot risk the millions of lives that might be lost if the Founders learn about the cure and the war is allowed to continue . Bashir coolly replies that Sloan no longer has any say in the matter . Ruefully acknowledging that he underestimated Bashir , Sloan activates a neuro - depolarizing device in his brain , killing himself . Act Two . Bashir stabilizes Sloan ' s body , but the higher cortical functions in his brain will cease within the hour , so Bashir prepares a multitronic engrammatic interpreter to link minds with the dying Sloan . This will allow him to see information through Sloan ' s memories , though the memories could be anything from Sloan ' s past , including his childhood . Miles insists on accompanying the Doctor on this potentially lethal travel through someone else ' s mind . Bashir explains to O ' Brien that when they are ready to exit , he will use his genetically - enhanced nervous system to raise his blood pressure , thus sending a signal to the device to pull them out . When they activate the mind link , they find themselves in a turbolift , which neither of them remember entering . They realize it is merely an abstraction in Sloan ' s mind . Act Three . The turbolift doors opens to a recreation of DS9 ; a cooperative Sloan greets the two , and seems to be aware of their place within his own dying mind . This Sloan tries to tell the two the cure , which is a simple nucleotide sequence but the dominant Sloan personality is preventing him from telling them what it is . He leads the two mind - travelers to a reception , being held in Sloan ' s honor , where he delivers a farewell speech to his family and friends , apologizing for all the pain he has caused in his life . After he finishes , he prepares to give Bashir and O ' Brien the cure on a PADD , but suddenly " another " Sloan appears , killing the first ( cooperative ) Sloan with a phaser , and running away down a corridor of Sloan ' s dying , yet still active , mind as cooperative Sloan ' s party disappears . Act Four . Bashir and O ' Brien receive phaser wounds from a character " guarding " Sloan ' s mind . The wounds are causing them physical pain , meaning that Sloan is sending sensory stimuli to their brains , as well as thought patterns . When Bashir is unable to disengage the mental connection , the two men fear they will die ( in reality ) because their minds are linked to a dying mind ; they ponder friendship , marriage , love . As O ' Brien wishes he had written Keiko a goodbye letter , Bashir confides that he loves Ezri , but has never told her . They then see . . . the light at the end of the corridor . They resist the urge to quit ; instead , they regain their bearing , and prepare to open another door . Suddenly , Bashir and O ' Brien wake up with Sisko , Worf , and Ezri around them . Bashir tries furiously to save Sloan and the knowledge of the cure , but it is no good and he dies . Act Five . Devastated , Bashir tells Odo that he has no hope of finding a cure . Odo thanks Bashir for all his help , asking to be left alone to die . Outside , Bashir and O ' Brien feel terrible that their plan failed but now there ' s nothing else they can do . The two friends part ways and sadly decide to turn in for the night . Later , Bashir tries to take his mind off the matter by reading Jadzia ' s copy of " A Tale of Two Cities " that Ezri loaned to him , but finds that after turning the page from where he left off , the book simply begins again from the start . Knowing the book can ' t be misprinted , Bashir realizes that he and O ' Brien are still in Sloan ' s mind , and that is another trick being played by Sloan , who is trying to keep Bashir and O ' Brien linked to him long enough to ensure that they will die with him . They remember they were about to open a door before their false awakening , and realize the cure must be there . When they finally reach the " inner sanctum " of Sloan ' s decaying mind , he tempts them with information tablets about every aspect of Section 31 that he knows . Bashir starts reading , and is shocked to find information powerful enough to bring the organization down . However , O ' Brien realizes that it is one final ploy by Sloan , knowing that one of Bashir ' s deepest desires is to destroy Section 31 . It ' s meant to distract them from finding the cure . Miles finds the correct tablet , and persuades Bashir to reluctantly walk away from the information . Bashir wakes up ( for " real " , this time ) in sickbay with Sisko , Ezri , and attending medical staff . O ' Brien awakens , and promises that will be the last mind link he is ever a part of . Sloan is dead , but Bashir has discovered the cure . Later , having synthesized the cure , Bashir injects it into Odo , who experiences a quick and complete recovery . Later that night , Bashir is playing darts again in Quark ' s , and O ' Brien comes by to invite the doctor to dinner . O ' Brien finds a bottle of the ' good stuff ' which is older than Bashir , and the two friends share a toast to ' aging gracefully and to Odo ' . Bashir accepts the dinner invitation , and reminds O ' Brien that Sloan had the perfect bait for Bashir with all the information on Section 31 , however O ' Brien was the one that saved him . The two drink another toast , this time to friendship and leave for the dinner which Keiko has prepared . Memorable quotes . " " Genocide – committed by people who call themselves Federation citizens . " " " " Remember these ? Romulan mind probes . Not the most pleasant devices , but very efficient . " " " " They ' re also illegal in the Federation . " " " " Oh , I hope you can appreciate the irony of " that " statement . " " " " I misread you . I thought you were just a misguided idealist . But you ' re a dangerous man . People like you would destroy the Federation . Fortunately , there are people like me who are willing to die in order to protect it . " " " " As I stand here , reunited with my friends and my family for one last time , I want you , the people I love , to know how sorry I am for all the pain that I ' ve caused you . I ' ve dedicated my life to the preservation and protection of the Federation . This duty , which I carried out to the best of my ability , took precedence over everything else : my parents , my wife , my children . I lived in a world of secrets , of sabotage and deceit . I spent so much time , erasing my movements , covering my tracks , that now as I look back on my life , I find nothing . It ' s as if I never really existed . I cheated you all out of being in my life , and what ' s more , I cheated myself as well . Now I know a simple apology won ' t change that . Still , I feel the need to apologize anyway . No tears , please . My death isn ' t a tragedy . It ' s a celebration . In death I can finally step out of the shadows , and prove to myself that I existed , that I lived . " " " " You ' re in a restricted area . " " " " I thought we were in the cerebellum . " " " " It ' s the tunnel . " " " " What tunnel ? " " " " Y ' know , the tunnel to the great beyond . " " " " It is . I must say I ' m a bit disappointed . I expected it to be a bit more elaborate . " " " " Hey Julian , the next time you take a trip inside someone ' s mind , you ' re going on your own . " " " " Aha ! Here we go . I knew Quark was hoarding a bottle of the good stuff . " " " " This is older than I am . " " " " What ? I ' m drinking with a child . " " " " I should warn you , you may feel some discomfort . " " " " If you mean it ' s going to be painful , just say so . " " " " It ' s going to be painful . " " Links and references . References . 47 ; adenine ; admiral ; Alamo ; alpha wave ; asporanine ; Bareil Antos ; cerebellum ; clerk ; computer expert ; cordrazine ; cortical stimulator ; ; ; darts ; ; doctor ; ethical issues ; Federation ; Founder s ; Great Beyond ; hippocampal nuclei ; hypothalamus ; hypothalamic feedback loop ; Jaresh - Inyo ; lidestolinine ; milligram ; morphogenic matrix ; morphogenic virus ; muffin ; neuro - depolarizing device ; Martok ; multitronic engrammatic interpreter ; neural interface ; neurotropan ; ; ; ; practical joke ; Qo ' noS ; Quark ' s ; radodine ; racquetball ; Romulan mind probe ; Section 31 ; security officer ; shock ; Sloan family ; sonic shower ; Starfleet Medical ; Starfleet Security ; suicide ; " " ; toast ; ; Vic ' s lounge ; Worf ( illusory ) Unreferenced material . holo - sculpture ; Tilavan art theft