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 above on 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 to come to the captain's office regarding an emergency transmission from a Cardassian Starfleet operative. Since most of the runabouts 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. Worf then brings up a mountain climbing expedition on Andor, but Dax 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 winning 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 sensors. Worf and Dax will need to land in Soukara's jungle, due to the Dominion's transporter scramblers, 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 six month 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 pilots 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 rifles.

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 Starfleet tricorders 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 with his adoptive father and brother Nikolai 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 Dax has been 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 operative as she continues to lose blood rapidly. 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 at a starbase 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 they 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 the sound of 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, turns around and heads back to Dax. By the time he gets to her she's unconscious, so he carries her on his back and begins the trek 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 bed in the infirmary 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.

Log entries 
 Shenandoah log

Memorable quotes 
"Esh'ta par'Mach'kai!!"
 - Worf, cheering Jadzia's tongo hand

"I didn't expect you to surrender so quickly."
"Surrender?!"
"Bad word."
"Very bad."
 - Dax and Worf

"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."
 - Dax and Worf

"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."
 - Lasaran and Dax

"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."
 - O'Brien and Bashir

"How are you enjoying your honeymoon? Are you suffering enough?"
"Almost."
"Anything I can get for you?"
"More pain, less cold."
 - Dax and Worf

"Genetically enhanced or not, you're only hew-mon."
 - O'Brien, to Bashir after his loss to Quark

"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."
 - Worf and Benjamin Sisko

Background information

Story and script
 The basic story of this episode, the idea of two officers journeying into a jungle behind enemy lines, was inspired by the 1968  and  movie , which also starred George Takei. ()
 After reading the script for this episode, Terry Farrell requested that Dax be killed now if she was going to be killed at all. At the time of production, she had already decided to leave the show following the end of season 6, as contract talks had failed to bring about a new contract for season 7, and she felt that having Worf complete the mission and leave Dax to die would create a very interesting character arc for him in the final season. According to Farrell, "I knew I wasn't coming back for the seventh season, so it was really written well, and it was the controversy of whether Worf should come back and save my life and not complete the mission, or complete the mission. But he decides to save his wife's life, and I remember thinking, 'Ah, this would be the perfect one to just end it'. I had asked not to be killed, but if you need to kill me because that's what you need to do, that would have been the perfect episode to do it because it would have been so much more for Worf's character to play in the long run, because he would have let his wife die, but completed the mission. Oh my God, what an awful thing to live with." (Crew Dossier: Jadzia Dax, DS9 Season 2 DVD special features) Jadzia was ultimately killed in the sixth season finale  by a Pah-wraith-possessed Gul Dukat.
 As with such incidents as Worf's decision to kill Kurn in , Kira's refusal to apologize to Silaran Prin in  and Odo's decision to allow an entire society disappear in , the writers saw this as another chance to take a character on an unexpectedly dark journey which would surprise the viewers. According to Ronald D. Moore, "I felt very strongly that we shouldn't let Worf off the hook when he's faced with a tough choice. So often in a story like this a character will get to have it both ways – his wife lives and he accomplishes the mission. They always cheat it somehow. But Worf was just not going to let Jadzia die out there in the jungle, so we decided to let him fail, to let that guy die and to let Worf take that hit. It represented a more interesting choice, and an unexpected decision on the part of the character." ()
 This episode's narrative structure is unique in Deep Space Nine insofar as the B-story (Bashir and O'Brien attempting to defeat Quark at tongo) ends just after the halfway point of the episode, and then the A-story takes over completely. Usually, A and B stories run concurrently for an entire episode. The reason writer Ronald D. Moore wrote the show this way was because he had been deeply unsatisfied with the results the last time he mixed a dark and serious A-story with a light-weight and inconsequential B-story; in the third season episode . According to Moore, "After Jadzia gets hurt, it gets so intense that we didn't want to break out and be cutting back." In , Moore had mixed an A-story involving the slow death of Vedek Bareil, with a B-story involving Jake and Nog on a disastrous double-date, and after the episode was completed, he came to feel that the farcical B-story really hurt the serious A-story. As such, he was determined not to make the same mistake again, so he purposely kept the B-story short and non-intrusive. ()
 The B-story for this episode originally involved Rom, Nog, and Prinadora. The plot involved Prinadora arriving on the station and claiming that she has come to reconcile with Rom and get to know Nog, but it turns out she's actually there to hood-wink Rom all over again. () Max Grodénchik, Aron Eisenberg, Chase Masterson, and Lolita Fatjo have performed the unfilmed B-plot at conventions.

Production
 The jungle of Soukara was created by the Greens Department on Stage 5 on the Paramount lot. Because there were so many walking shots, the jungle was built as a large circle so that the actors and crew didn't have to keep stopping and switching sides every time they reached the 'end'. However, during shooting, the general consensus was that the Greens people did too good a job in constructing the oppressive jungle. According to art director Randy McIlvain, "We had designed small platforms to put all these trees on, so that the filmmakers could move the platforms out and get into the jungle area to shoot. But they added more and more plants, until we couldn't move the platforms! The plants and vines were all intertwined." As Steve Oster points out, "It got so difficult that we might as well have been on location." ()
The episode features Jadzia piloting the Shenandoah through an asteroid belt to get to Soukara. Commented David Stipes: "I thought the asteroids were really nice. We were initially [thinking] about using the asteroids from  which was a Voyager episode that we had done some years ago. You can wind up copying yourself if you're not careful, and all of a sudden you wind up doing your own shots over and over, and you're not 'pushing your own envelope' so to speak. I've been working with the idea of finding new ways to be creative. It would be very easy to fall until this trap of, 'We've done that before. What did we do before? Let's do the same thing.' It's much more fun and challenging to say, 'How can we make this asteroid field look a little different?' The guys at Digital Muse were just great. They just kept pushing at it, and tweaking, looking at textures, painting and showing things. I would share ideas, and Adam would share ideas. It's a wonderful collaborative effort, and I really enjoy this process a lot." (Cinefantastique, 146, Vol 30 #9/10, 1998)

Reception
 Ira Steven Behr says of this episode, "This was the episode that was going to show that the love Worf has for Dax goes beyond his Klingon upbringing, and even beyond his Starfleet training. That was a bold step to take with a character who had previously been defined by these very two elements." ()

Trivia
 This was the 500th episode of Star Trek to air. 
 This episode reintroduces the notion that Bashir is still madly in love with Dax, something which has its origins in the very first episode of the series, . Bashir's realization here that he still loves her however would finally pay off in the series finale, , albeit with Ezri Dax as opposed to Jadzia Dax.
 This episode marks the first appearance of Deep Space 9's newest  runabout, the , and the Dominion-held planet of Soukara, which is later referred to in .
 This episode contains the only reference to Worf's adopted brother Nikolai Rozhenko since his appearance in .
 When they are in their quarters getting ready for bed, Dax tells Worf that the  will be docking at the station. This is the same ship that was at the station during the episode  and aboard which Manuele Atoa serves as a lieutenant. This is also the same ship commanded by Data during the Klingon Civil War in .
 Casperia Prime is mentioned for the first time in this episode as Dax's intended honeymoon destination.
 Rene Auberjonois (Odo) and Cirroc Lofton (Jake Sisko) do not appear in this episode.

Remastered version
Remastered scenes from the episode are featured in the documentary What We Left Behind.

Apocrypha 
 The events of this episode are an important part of the novel , when Worf rejects Captain Picard's decision to make him the new first officer of the  – following Commander Riker's promotion and Data's death – because he feels that he does not deserve the command after his actions here. However, when Picard is briefly re-assimilated by the Borg, Worf nevertheless takes command, successfully destroying the Borg drones on the enemy cube and rescuing Picard, Doctor Crusher simultaneously managing to "infect" the Borg Queen with a "virus" that will prevent the Collective from creating a new one.
 The events of this episode are referenced when Worf meets Ezri Dax – Jadzia's "successor" as the Dax host – during the Star Trek: Destiny trilogy; with Ezri now a captain and Worf a first officer, she expresses concern that Worf's lower rank is the result of him saving Jadzia, but Worf assures her that she does great honor to Jadzia's memory with her career and that he has nothing but respect for her.
 The events are also briefly referenced in the Star Trek: Picard novel The Last Best Hope, raised as a token objection before Worf is promoted to captain of the Enterprise-E.

Video and DVD releases 
 UK VHS release (two-episode tapes, CIC Video): Volume 6.8, 
 As part of the DS9 Season 6 DVD collection

Links and references

Starring 
 Avery Brooks as Captain Sisko

Also starring 
 Rene Auberjonois as Odo
 Michael Dorn as Lieutenant Commander Worf
 Terry Farrell as Lieutenant Commander Dax
 Colm Meaney as Chief O'Brien
 Armin Shimerman as Quark
 Alexander Siddig as Doctor Bashir
 Nana Visitor as Major Kira

Guest star 
 Todd Waring as Lasaran

Uncredited co-stars 
 David B. Levinson as Broik
 Tom Morga as Jem'Hadar soldier
 Chester E. Tripp III as Jem'Hadar soldier
 unknown stunt performer as Jem'Hadar soldier

References 
21st century; 2367; advisor; Alpha Quadrant; Americans; amusement; Andor; anti-coagulant; asteroid field; Badlands; bandage; bedside manner; blood pressure; bloodwine; ; Cardassia Prime; Cardassians; career; Casperia Prime; ; chiffon; coach; darts; disruptor burst; Dominion-controlled space; evasive maneuvers; Ferengi; finger; first aid; Founders; funny (aka sense of humor); god; heart; Highlands; Horvian Cluster; humor; Istanbul; Jem'Hadar; joke; joule; jungle; kayaking; kilometer; Klingonese; latinum; leverage; local time; "long shot"; mating call; mek'leth; medical tricorder; medkit; meter; MI5; mountain climbing expedition; neural EDL; night watch; ; operative; "out of reach"; ; painkiller; par'Mach'kai; plasma; Quark's; Queen of England; rhinestone; Risa; Romulan; room service; ; ; runabout; Scotch whiskey; sensor perimeter/sensor grid; "show all one's cards"; ; Soukara; Soukara base; Soukara system; South Pacific; s; Starfleet Bureau of Information; Starfleet Intelligence; stasis chamber; starbase; summer; Union of Soviet Socialist Republics; tongo; tongo player; topographical map; topographical scan; tricorder; Ural Mountains; vital organs; Vorta; Vorta advisor; Vulcan's Forge; wedding; West Berlin; wink; wolf; year

Starship references 
; ; Ninth Fleet; ; ; ;

External links 
 
 
 
 

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DS9 episodes