Marge plans to throw a dinner party to escape from the doldrums of everyday life at the Simpson house. She invites the Flanders, the Lovejoys, the Hibberts and the Van Houtens. The parents enjoy dinner except for the Van Houtens who nitpick at each other all night as Milhouse plays upstairs with Bart and the other kids. Kirk and Luann get more quarrelsome as the party progresses and finally, despite Marge trying to divert the party away from the fighting pair, the two get into a fight and Luann demands a divorce.
Kirk moves out of the Van Houten house and despite his drab new surroundings, he keeps a cheery attitude toward it all, until he is fired from his job at the cracker factory. His former father-in-law explains that the cracker factory caters to happy families, not miserly singles. Meanwhile, Luann quickly readjusts to singles life and starts a new relationship with Chase, an American Gladiator. Kirk also tries to have a new relationship, but is unsuccessful as his girlfriend, Starla, leaves him along his car. While outside at Moe's, Kirk mentions that he never saw the divorce coming and regretted not having catered to Luann's needs. Homer tries to cheer him up by telling him that his marriage to Marge is strong. Kirk is less than encouraged and warns him to appreciate Marge while he still can. However, Homer begins to fear that his marriage to Marge might be next, when Homer comes home and sees frozen hot dogs on thawing in the sink.
Homer enlists the aid of Lisa to help him figure out how to save his marriage. When she asks him what is wrong, Homer recalls both his wedding and reception which was nothing more than him and Marge at a truck stop eating a whale cake. Homer realized how disappointed Marge was because she had been hoping that their family and friends would jump out and yell surprise. Lisa can only tell her father that he is lucky to have Marge in his life. Homer tries to perform selfless gestures for Marge, such as making "soothing" ocean noises to lull her to sleep, but Marge acts indifferent. When he attempts to cut her hair, Marge finally loses her patience and tells him to leave her alone.
Thinking that their marriage is finished, Homer secretly files for a divorce from Marge. As Marge returns home later that night from Bart's dental appointment, Homer surprises her by hiding all their friends in the living room and declares that he wants to be remarried, this time with a perfect wedding. Marge is deeply moved, and assures Homer that he doesn't have to do this. Homer says that he has to because he already filed for their divorce that afternoon. The two are remarried and, inspired by Homer and Marge, Kirk plans to try to get back together with Luann by singing a song he wrote. This fails when Luann objects and Kirk is escorted out of the Simpsons house by Chase.
During the end credits, a sax version of the theme song is played.