-->'''Dax''': ''[to Worf]'' It sounds like you have a bad case of par'Mach.\\
'''Sisko''': Is that contagious?\\
'''Dax''': ''Par'Mach'' is the Klingon word for "love", but with more aggressive overtones.

Bashir and Quark eavesdrop on a domestic argument coming from O'Brien's quarters, but they're met by Keiko in the hall, revealing that the chief has been arguing with Kira this whole time. Later, Worf and Dax discuss Klingon opera at the replimat when Worf spots a beautiful Klingon maiden and falls instantly in love. He ditches Dax and follows her to Quark's, where she embraces Quark as an old friend. It turns out that she's Grilka, the Klingon noblewoman [[Recap/StarTrekDeepSpaceNineS03E03TheHouseOfQuark whom Quark briefly married]].

Grilka has come to Deep Space Nine to get some financial advice from Quark, though Klingon rules of etiquette require Quark to volunteer his help on his own. In spite of their cultural differences, the AmicablyDivorced couple enjoy each other's company. But Worf wants her for himself. He picks a fight with Grilka's bodyguard Thopok as a means to court her, but her chamberlain takes him aside to politely remind him that a match between a Klingon noblewoman and an outcast is impossible. Shamed, Worf slinks away.

Meanwhile, O'Brien and Kira are still squabbling as the chief tends to her hand and foot to ensure the health of his unborn child. Bashir cracks jokes about how physically involved O'Brien has become with Kira, which the chief finds annoying. But in the midst of a massage, the pair realize that their relationship is in fact dangerously close to becoming a romance. All the while Keiko obliviously continues to support their behavior.

Quark seeks Dax for help in seducing Grilka. She teaches him traditional Klingon courtship and trains him in a holosuite program that is considered romantic. Grilka is impressed and asks him why he's pursuing her. He says that, as a Ferengi, he prizes things of great value. This is too much for Thopok, who challenges Quark to a duel. Meanwhile, Kira decides to create some distance from O'Brien by going on vacation. [[DramaticallyMissingThePoint Still oblivious to their budding romance]], Keiko insists that O'Brien accompany her to keep their baby safe.

Dax and Worf help Quark by rigging up some [[NeuralImplanting neural implants]] that allow Worf to move Quark like a puppet. Although still disdainful of the Ferengi's advances on Grilka, Worf fights for Quark during the duel and holds his own until the link breaks. Without Worf's help, Quark is dead meat, so he stalls by insisting on his Ferengi right to deliver a speech. Grilka decides to honor his request. Quark launches into a [[HoldingTheFloor rambling filibuster]] while, just next door, Dax scrambles to repair the neural link. When it's fixed, Quark abandons his speech and promptly defeats Thopok with Worf's help. Unaware of what to do now, Quark lets Worf puppet him into handing Thopok's bat'leth to Grilka, who restores it to Thopok and dismisses him from her service with his honor intact. Quark and Grilka then depart for some alone time.

As O'Brien and Kira prepare to go on their unwanted vacation on a runabout, Kira reveals that their destination is perhaps the most romantic destination on Bajor. In spite of their obvious attraction, they decide to make up an excuse for O'Brien to skip the vacation and so nip this romance in the bud. They agree it would have been nice "in another life" before Kira urges O'Brien to [[GetOut get the hell out]].

Worf is still resentful of helping a Ferengi score a Klingon, but Dax angrily states that Quark saw an opportunity when it presented itself, which Worf himself has failed to do. Worf still doesn't get the signals that Dax is sending him, so she spits some Klingon fighting words at him and tosses him on his ass. Finally on the same wavelength, Worf and Dax get down for some traditional Klingon DestructoNookie. Later, both couples arrive at sick bay to tend their post-coital wounds, and Bashir decides not to ask questions about what they've been doing

!Tropes:

* AbductionIsLove: The way Quark and Grilka met.
* AmicableExes: Quark and Grilka.
* ApologeticAttacker: Worf whispers to Morn, "I will apologize for this at a later time" before tossing him off a bar stool and shouting "You are in my seat!" to [[WomenPreferStrongMen impress Grilka]].
* AppliedPhlebotinum: The puppeteering device Worf uses to control Quark during ritual battle.
* AsYouKnow: After Worf falls for Grilka and learns that she's Quark's ex-wife, Dax explains to him (and the audience) the circumstances that led to that predicament. It's justified however, since Worf wasn't on the station when this originally happened.
* BattleCouple:
** Quark charms Grilka by going to the holosuite to reenact the story of Kahless and Lukara, the ultimate Klingon BattleCouple. Quark is pretty much a failure in battle, but Grilka appreciates his effort and warms up to him.
** Also Worf and Dax; this is the beginning of their relationship.
* BelligerentSexualTension:
** O'Brien and Kira start the episode arguing constantly. They nearly fall in love by the end of the episode.
** Dax and Worf are amicable up until Dax gets fed up of him being ObliviousToLove, causing them to argue.
* BreatherEpisode: A Klingon-style romantic comedy between two episodes with lots of fighting and death.
* ButIReadABookAboutIt: Worf may not be a natural at charming Klingon women but he knows everything there is to know about Klingon culture--including the mating rituals of obscure provinces like Grilka's.
* {{Callback}}: Dax relates the events of [[Recap/StarTrekDeepSpaceNineS03E03TheHouseOfQuark The House of Quark]].
* TheConsigliere: Tumek, Grilka's Chamberlain.
* CouldSayItBut: The reason Grilka has come to see her ex is because her House is having financial problems and she needs Quark's business acumen. Of course a proud Klingon warrior would never stoop to asking for advice from a Ferengi, but Quark picks up her hint and casually suggests that he take a look at her books, which Grilka graciously allows.
* DeliberateValuesDissonance: The A-plot is driven by the intricacies of Klingon courtship, which is alien to both Human and Ferengi.
* DestructoNookie: And poor Bashir has to repair the damage.
* DuelToTheDeath: Quark duels Thopok for Grilka's affections.
* FantasticRacism: Grilka's bodyguard, perhaps affected by a [[LoveMakesYouEvil dark version]] of BodyguardCrush.
* FirstNameBasis: Odo points out that Kira keeps referring to O'Brien as "Miles" rather than "the Chief."
* FishOutOfWater: Quark, but to his credit he does his best to catch up.
* FriendsWithBenefits:
** Quark and Grilka.
** As with K'Ehleyr, Worf points out to Dax that traditionally they should get married after having sex. Given his CharacterDevelopment since then, he (albeit reluctantly) agrees with Dax's suggestion that they take it one day at a time and see what happens.
* GetOut: Kira says this to O'Brien before he leaves the runabout.
* GoingNative: Quark of all people, temporarily goes native with Klingons.
* HoldingTheFloor: Quark plays for time after the mimic device shorts out and he's lost Worf's bat'leth skills in the duel. He demands the (non-existent) Ferengi "Right of Proclamation" and starts improvising love poetry on the spot, until Worf gets it working and Quark abruptly finds himself fighting again.
* ItOnlyWorksOnce: After being challenged to a duel to the death by Grilka's bodyguard, Quark briefly contemplates using the same tactic he used successfully against D'Gor the last time around, of throwing down his weapon and daring his opponent to kill him in a dishonorable manner. Worf quickly points out this only worked last time because it was a public display of dishonor in front of the High Council, causing Gowron to step in and stop D'Gor. In the case of a private duel there's nothing to stop Quark's opponent from simply executing him anyway.
* IWantMyBelovedToBeHappy: Played with. Worf not only accepts rejection but helps bring Grilka together with Quark, though it's also to [[PlayingCyrano prove to himself that he really can court a Klingon woman]].
* KnowWhenToFoldEm: Worf makes a spirited attempt to impress Grilka, but when her chamberlain forces him to realize how unacceptable a mate he'd make for her, he bows out as gracefully as possible.
* MandatoryLine: Sisko only appears briefly at the beginning to ask if par'Mach is contagious.
* ManlyMenCanHunt: Courtship begins with the male SweepingTheTable and presenting the leg of a beast he slew to the female, declaring in a [[LargeHam loud voice]] his intent to provide for her family. She either accepts the offer or orders her bodyguard to break the suitor's bones, and not in a DestructoNookie fashion.
* TheMatchmaker: Jadzia and Worf try to help Quark win over Grilka.
* MatchmakerCrush: Inverted with Worf and Jadzia. He already has a crush - but it's in this episode he [[ObliviousToLove finally realises]] the matchmaker's into him.
* MomentKiller: Worf gets Grilka's attention at first, but the Chamberlain politely interrupts to tell Worf that he has no chance due to his Family's disgrace.
* {{Mythopoeia}}: ''A thousand years ago it was the dawn of the Empire. Five hundred warriors stormed the Great Hall at Quam Chee. Only the Emperor Kahless and the Lady Lukara stood their ground. It was here that they began the greatest romance in Klingon history.''
* NoTrueScotsman: A milder example than most, as Tumek isn't being overtly antagonistic, but he does tell Worf that his Federation upbringing makes him ill-suited to court a Klingon woman.
-->'''Tumek:''' Have you ever pursued a Klingon woman?\\
'''Worf:''' No.\\
'''Tumek:''' There's no shame in that. You were raised by Humans, you wear their uniform, you accept their values. How could you know anything about our women?\\
'''Worf:''' You'd be surprised what I know.\\
'''Tumek:''' Perhaps. But we will not find out here. It is the wish of the Lady Grilka that you leave us now, son of Mogh, and do not return.
* ObliviousToLove: Worf's obliviousness to Jadzia's attraction to him ''finally'' ends.
* OhCrap:
** Quark when the puppeteering device is broken.
** O'Brien and Kira, in the midst of their grown UST, when they realize that they are heading for [[MakesSenseInContext a romantic forest getaway together]].
* PintSizedPowerhouse: Despite clearly being miserable, Quark actually does decently during the holodeck simulation fight (especially when you consider he has no combat training and apparently never exercises), and with Worf piloting him his body is at least physically capable of going toe-to-toe with a Klingon warrior and winning despite his significant height disadvantage.
* PlayingCyrano: Dax trains Quark in how to woo Klingon matriarch Grilka, the Ferengi's one-time wife. Worf is also recruited to help, though he does so reluctantly.
* PregnancyMakesYouCrazy: No, it just makes Bajoran women sneeze a lot.
* ThePowerOfTrust: If any wife trusted her husband as much as Keiko did it would take the most utter wretch in the universe to hurt her. Fortunately neither Miles nor Kira are utter wretches.
* ReasonableAuthorityFigure: When Worf starts to court Grilka, her chamberlain quietly takes him aside and politely explains why he would not make a suitable mate for her.
* RelationshipUpgrade: While they had been flirting on and off, this marks the true beginning of Worf and Dax's relationship.
* SequelEpisode: To [[Recap/StarTrekDeepSpaceNineS03E03TheHouseOfQuark "The House of Quark"]].
* SlapSlapKiss: Worf and Dax fight before they get down to it.
* SwordOverHead: When Quark wins, his opponent tells him to GetItOverWith. Quark is only too willing to oblige, but Worf forces him to [[BattleTrophy take Thopok's sword and present it to Grilka]].
* TooMuchInformation: Bashir when Quark not-so-subtly hints at what he and Grilka were doing that landed them in the infirmary. And again when Worf and Jadzia show up looking like hell, with Jadzia [[SexyShirtSwitch wearing Worf's baldric]].
-->'''Bashir:''' A compound fracture of the right radius, two fractured ribs, torn ligaments, strained tendons, numerous contusions, bruises and scratches. What ''have'' you been doing?\\
'''Quark:''' You mean...''(looks at Grilka)'' what have ''we'' been doing? ''(they both laugh)''\\
'''Bashir:''' ''(grimaces)'' Never mind. I don't need that particular image running around in my head. I'll just treat you. ''(sees Worf and Jadzia enter)'' What happened to you two?\\
'''Worf:''' We, er…\\
'''Jadzia:''' Well, er...i-if you must know--\\
'''Bashir:''' No! No, I don't need that image, either. In fact I'm gonna stop asking that question altogether. People will come in, I will treat them, and that's all.
* WarriorPoet: Worf tries to teach Quark how to be a WarriorPoet. Oddly enough he succeeds. Sort of.
* WaxingLyrical: Quark muses, "War, what is it good for? If you ask me, absolutely nothing." Of course, this is a light paraphrase of the chorus of Edwin Star's song "War (What Is It Good For)."
* WhatYouAreInTheDark: Miles and Kira come damn close to having an affair behind Keiko's back, but break it off before it goes that far.
* {{Worldbuilding}}: Worf tells Quark about several Klingon customs and legends.
* YouDoNOTWantToKnow: Bashir does this to himself after he idly asks what Quark and Grilka have been up to. And then when Dax and Worf show up shortly after.