Change of Heart ( episode ) On a mission to recover a Federation informant on the Dominion world of Soukara , Dax is injured and Worf must choose between completing the mission or saving his wife . Meanwhile , O ' Brien enlists Bashir ' s help to defeat Quark in a game of tongo . Summary . Teaser . On Deep Space 9 , tongo has recently been going well for Quark . He has won two hundred and six straight games in the last month . This night , Jadzia Dax is playing at Quark ' s bar , with Worf and Miles O ' Brien watching from the second floor . The two make a bet on Dax ' , though she barely loses against Quark . Worf now owes O ' Brien a bottle of Scotch whisky , though he doesn ' t feel bad . When he goes down to see her , he tells her he would rather lose betting on his wife than win betting on someone else . In the middle of the following night , Kira calls for Worf and Dax regarding an emergency transmission from a Cardassian Starfleet operative . Since most of the runabout s and the are off on exercises with the Ninth Fleet , the couple must embark on a trip into the Badlands ( where they will be able to contact the Cardassian ) aboard the . Act One . On their way to the Badlands , Worf and Dax discuss plans about their honeymoon . Worf suggests Vulcan ' s Forge as a suitable location , however Dax shoots it down instantly as she doesn ' t want to spend her honeymoon in the Forge during ' s summer . She instead demands a relaxing vacation on Casperia Prime , arguing that Worf got to plan the wedding so she should get to choose the honeymoon . . . and is surprised when Worf accepts her argument and instantly agrees . After that , the conversation orients itself around a discussion about Worf ' s sense of humor and various habits and tolerance to change of the two of them – nothing very deep , but there ' s a sense of the bond that has developed between the two of them . Back on the station , Julian Bashir arrives promptly at O ' Brien ' s quarters in a tuxedo for another of their holosuite adventures , but O ' Brien is occupied . Ignoring it , Bashir briefs O ' Brien on their mission , however , he realizes O ' Brien isn ' t paying attention and sits down , disappointed . Due to Quark ' s long running streak , the chief has been inspired to set his mind to a new challenge : to end Quark ' s streak . When Bashir realizes that he won ' t be able to get O ' Brien up , the doctor accepts helping his friend practice the game for a bit . Soon after they arrive at the coordinates in the Badlands , Worf and Dax receive a transmission from the Cardassian operative , Lasaran . The spy , disappointed to see a Klingon , informs them that he has information on every single Founder in the Alpha Quadrant . In return , he wants out immediately , as he is not secure any more . Furthermore , he can ' t wait , so demands the two come immediately , sending them extensive data about a rendezvous point near a Dominion base on Soukara , complete with instructions on avoiding its sensor s . Worf and Dax will need to land in Soukara ' s jungle , due to the Dominion ' s transporter scrambler s , to recover the informant . The two agree , and , with a regret on trusting the word of a Klingon , Lasaran ends the communication . Act Two . After a while practicing , it ' s clear O ' Brien isn ' t getting the hang of the game and Bashir is able to defeat him handily , though he just learned the game himself . Bashir tries to persuade him that he has no aptitude for tongo . O ' Brien is determined to keep practicing , noting the challenge of it ( and Keiko ' s absence ) , but he soon decides to change his plan ; instead , Bashir , with his genetically - enhanced brain , should be able to easily beat Quark . Bashir clearly doesn ' t care about the game or the latinum , but is convinced when the look on Quark ' s face at being beaten by a Human is offered as a reward . Meanwhile , Dax successfully pilot s the " Shenandoah " through an asteroid field , where the sensor grid has its gaps , with her usual teasing since she ' s going fairly quickly . Worf is not nervous , though . She then evades detection from the planet ' s sensors and takes to finding a landing point . They ' ll need to land 20 km north of the rendezvous to keep away from ground sensors , and have only two days to cover the distance . They land on Soukara and head out with their gear , including phaser rifle s . Act Three . Dax and Worf successfully mask their lifesigns from sensors on the ground . They have some banter as they set out , as Worf comments they can ' t use their tricorder s while it masks their lifesigns , but he is looking forward to not knowing what lies ahead . Meanwhile , Bashir and O ' Brien are finally ready to challenge Quark . Even though the Ferengi are reluctant to admit Humans to their table at first , they eventually accept . Eventually , there is only Bashir and Quark left at the tongo table , the bartender congratulating the doctor on his fast learning . Nevertheless , Quark has another card in his sleeve and soon begins a conversation about Bashir ' s past feelings for Dax and is able to distract the doctor long enough to drag him into a ruining confrontation against what finally reveals to be a total monopoly . Dax and Worf carefully progress through the grueling jungle without incident . They camp that evening , listening to the indigenous wildlife and Worf relating his childhood trips to the Ural Mountains and the joy of listening to the wildlife . However , soon , Worf senses something coming from the changing noises of the wild . They hide as a patrol of three Jem ' Hadar approaches . They kill all three , but Jadzia is hurt by a disruptor burst which leaves an anti - coagulant in her system leaving her at the risk of bleeding to death . Despite this , the two of them push onward , as the patrol ' s absence will be noticed . Act Four . The two continue through the jungle , but it becomes increasingly clear that Dax will not be able to make the rendezvous with the Cardassian agent as she continues to lose blood . She is determined to go as far as she can while making light of the situation , however , she ' s frustrated when Worf doesn ' t reciprocate . He ' s in the seriousness of the moment , regretting letting his guard down earlier and not staying vigilant . Dax is determined to go as far as she can , waving off Worf ' s help in walking . She eventually can ' t walk and sits down . With four bandages changed in two hours , her wound is hard to ignore . With another light comment to get Worf to smile , she tries to settle herself . Worf responds he will smile all she wants when the mission is over . Worf says they have three kilometers left and Dax tries again to stand , but , finally , Dax is unable to stand , even with a hypo . Act Five . Dax ' s medical readings are becoming increasingly erratic and it ' s clear she requires surgery as soon as possible if she is to have any chance of surviving . The two agree that the information Lasaran has is invaluable and they both have a duty as Starfleet officers to ensure it gets delivered . However now Worf has to leave Dax behind in order to continue the mission , telling her he can return with Lasaren and get her into the runabout ' s stasis chamber within 45 hours although both know she will likely be dead by the time he returns . They share a heartfelt goodbye as Worf leaves . As he heads towards the rendezvous , the sounds of the jungle and animals are drowned out as Worf can only hear his own heart beating . Eventually it gets to the point where Worf cannot proceed any further knowing his wife is dying . He decides to abort the mission , and heads back to Jadzia . By the time he gets to her she ' s unconscious , so he carries her back to the runabout . Back on Deep Space 9 , Dax gets the health care she needs . However , things do not go as well for her husband : his actions have led to Lasaran ' s death . Captain Sisko demands an explanation , and Worf tells him that as he went further and further into the jungle , he knew that he there was no way he could leave his wife behind , even knowing that he would almost certainly be ending his career as well as costing Starfleet the intelligence that could have saved millions of lives . Sisko tells Worf that the secrecy of the operation and Starfleet ' s desire to keep their intelligence activities under wraps will save him a court martial , but there will be a permanent note in his service record . As a result , Worf will almost certainly never be offered a command of his own after the incident . Sisko also issues orders that Worf and Dax are to be " never " sent on a mission alone again . However , off the record the captain tells Worf that as a man who once had a wife , that if it had been Jennifer lying there in the clearing , he would have made the same choice . Worf visits the recovering Dax in her hospital bed and tells her that he didn ' t complete the mission . Dax is sorry that he hurt his career because of her , but Worf tells his wife that he isn ' t sorry as she is what matters , above his career and everything else and that if the situation arose again he would do exactly the same again . The two then reaffirm their love for each other . Memorable quotes . " " Esh ' ta par ' Mach ' kai ! ! " " " " I didn ' t expect you to surrender so quickly . " " " " Surrender ? ! " " " " Bad word . " " " " Very bad . " " " " Worf , you ' re practically easygoing . What ' s next ? A sense of humor ? " " " " I have a sense of humor ! On the " Enterprise " I was considered to be quite amusing . " " " " That must have been one dull ship . " " " " That is a joke . I get it . . . it is not " funny " , but I get it . " " " " A Klingon . Why do they have to send a Klingon ? " " " " I ' m a Trill , does that make you feel any better ? " " " " Are you trying to be funny ? " " " " Not at all , he ' s the funny one . " " " " Think of it as a challenge . " " " " That ' s your obsession , Miles , not mine . " " " " Do it for the latinum . " " " " Nice try . " " " " Do it for the satisfaction of the look on Quark ' s face when he ' s beaten at a game of tongo by a lowly hew - mon . " " " " Deal the cards . " " " " How are you enjoying your honeymoon ? Are you suffering enough ? " " " " Almost . " " " " Anything I can get for you ? " " " " More pain , less cold . " " " " Genetically enhanced or not , you ' re only hew - mon . " " " " You were at my wedding . You heard the story of the first two Klingon hearts and how nothing could stand against them , and how they even destroyed the gods that created them . I have heard that story since I was a boy , but I never understood it , I mean really understood it , until I was standing in the jungle with my heart pounding in my chest and I found that even I could not stand against my own heart . I had to go back . . . and it did not matter what Starfleet thought or what the consequences were . She was my wife and I could not leave her . " " " " As your captain , it is my duty to inform you that you made the wrong choice . I don ' t think Starfleet will file any formal charges . Even a secret court - martial would run the risk of revealing too much about their intelligence operations . But this " will " go in to your service record . . . and to be completely honest , you probably won ' t be offered a command on your own after this . " " " " I understand . " " " " I have also issued new orders . You and Jadzia are not to be assigned to a mission on your own " ever " again . And one last thing . As a man who had a wife , if Jennifer had been lying in that clearing , I wouldn ' t have left her either . " " Links and references . References . advisor ; Alpha Quadrant ; American s ; Andor ; anti - coagulant ; asteroid ; bandage ; bedside manner ; bloodwine ; ; Cardassia Prime ; Cardassian s ; Casperia Prime ; chiffon ; coach ; darts ; disruptor burst ; ; evasive maneuvers ; Ferengi ; Founder s ; Horvian Cluster ; Istanbul ; Jem ' Hadar ; joule ; kayaking ; latinum ; mating call ; " mek ' leth " ; medical tricorder ; medkit ; meter ; MI5 ; Ninth Fleet ; ; overseer ; kilometer ; " par ' Mach ' kai " ; plasma ; Quark ' s ; Queen of England ; rhinestone ; Risa ; Romulan ; room service ; ; ; runabout ; Scotch whiskey ; ; ; Soukara system ; Starfleet Bureau of Information ; Starfleet Intelligence ; stasis chamber ; starbase ; ; Union of Soviet Socialist Republics ; tongo ; tricorder ; Ural Mountains ; vital organ s ; Vorta ; Vorta advisor ; Vulcan ' s Forge ; West Berlin ;