With bar business especially slow, Rom complains to Quark that their only customer, a Klingon named Kozak, says he's out of money. Quark approaches Kozak, who responds by pulling a knife. But he is so inebriated that he trips and falls on the blade, killing himself. Quark is horrified, but when the bar is flooded with patrons flocking to see what happened, he recognizes a good business opportunity and takes credit for killing Kozak in self-defense. Thrilled with his newfound popularity, he ignores Odo's warning that Kozak's family might retaliate. Sure enough, D'Ghor, Kozak's brother, soon arrives and collars Quark.
A fearful Quark prepares to tell D'Ghor the truth, but learns that his life would be spared only if Kozak died honorably in battle. Thus sanctioned, Quark continues to revel in his role as a "slayer of Klingons" until Grilka, Kozak's widow, arrives and realizes the Ferengi is lying. She takes Quark to the Klingon home world against his will, where she explains that a provision in Klingon law grants consideration to a female left without a male heir after the accidental death of a spouse. This might allow her to lead her own House. But since Kozak instead died "in battle," the lack of a male heir would cause the House of Kozak to fall, and D'Ghor, who has been enemies with his brother's family for years, could take over. Unwilling to let that happen, Grilka conducts a ceremony where Quark winds up married to the widow.
Grilka brings Quark before the Klingon High Council and presents Quark as her husband, reminding the Council that, as Kozak's killer, Quark may be invited to take his place, and his wife. Much to the chagrin of D'Ghor, Council leader Gowron promises to consider her words, allowing the House of Kozak to be known as the House of Quark until he reaches a decision.
Grilka is not certain what to do next, until Quark volunteers to go over the financial records of the House. He discovers that D'Ghor has been systematically attacking Kozak's family's assets for years, weakening the House in order to prime it for a takeover. Together, Quark and Grilka present their findings to the High Council. But instead of conceding defeat, D'Ghor demands vengeance through personal combat, revealing that Quark lied about Kozak's death by bringing in Rom as a surprise witness.
With his life now on the line, Quark decides to run rather than face D'Ghor in battle. This means Grilka must return to Gowron without a husband, and with little chance of stopping D'Ghor from taking everything she has. Surprisingly, however, Quark arrives at the Council meeting armed to fight. As D'Ghor prepares to attack him, Quark suddenly tosses away his bat'leth sword, then reminds the Council that killing a defenseless Ferengi would be an execution instead of a honorable victory. An unmoved D'Ghor prepares to deliver the death blow anyway, but Gowron stops him, ashamed by his total lack of honor. Gowron then grants Grilka special dispensation to lead her House on her own. Quark is given a divorce, and he returns to Deep Space Nine a true hero in his brother Rom's eyes.