Marge chooses an oversized jigsaw puzzle of a San Francisco concert scene for the family’s weekly activity. At first, Bart and Homer complain about the puzzle, but they soon become addicted to completing the gigantic task, and over a week later the puzzle is finally finished—except for one missing piece. The family searches for it high and low, leading Homer to the closet in his bedroom, where he discovers an old placemat from Moe’s bar. On the back of the placemat is a letter, written by Marge in the 1970s, when she and Homer were dating. In the letter, Marge complains that Homer left her alone at a table while he and his friends played video games. She concluded at the time that their relationship could never work. A short time later, Marge announces that she found the missing puzzle piece. But Homer’s mind is on the letter. He asks Marge if she still believes he ruined her life. She admits that some of the things he does drivers her crazy. Miffed, Homer decides to sleep in Bart’s bed that night.

The next morning, Homer fixes his own breakfast. Marge encourages him to forget about the letter, as they’ve been married for ten years. Insisting he can no longer live with Marge, Homer packs his belongings and moves out. He relocates to Bachelor Arms, where he moves in with Kirk Van Houten. But the constant sobs of lonely men drives Homer out. He makes his way back to his neighborhood, but walks up to the wrong house, which, it turns out, is where his old assistant, Karl, a gay man, is now living. When Homer tells Karl about his dilemma, Karl takes him for a ride to another section of town, a gay neighborhood filled with beautiful Victorian homes. Karl introduces Homer to two of his friends, a gay coupled named Julio and Grady, who share an apartment in the neighborhood. At first, Homer is shocked at the idea of sharing an apartment with two gay men. He decides to drink some beer and stay the night to give the arrangement some thought. The next morning, Homer eats one of Grady’s delicious breakfasts and makes the decision to move in. Soon after, Homer is hanging out with Grady and Julio at their favorite gay nightspots.

Meanwhile, Bart and Lisa encourage Marge to patch up her differences with Homer so life can return to normal. When Marge and the kids make their way to the apartment for a visit, Marge pulls Homer aside and tells him she loves him—and thinks it’s time for him to come home. But Homer maintains that living with Grady and Julio has been a great experience. He tells Marge he may never come back to her. Marge tells Grampa about her dilemma. He tells her that if she wants to win Homer back, she’ll have to romance him. Marge turns to Weird Al Yankovic for help. As Homer listens from the apartment window, Weird Al sings “Jack and Diane” with alternate lyrics. Impressed, Homer tells Marge he’ll go out on a date with her. Later, as Homer prepares for the date, Grady and Julio realize he’s nervous. They give him some margaritas to calm him.

Meanwhile, an embarrassed Marge waits for Homer at Medieval Times, a castle-like restaurant with a medieval theme. When Homer eventually shows up, he’s drunk. Marge storms out. Homer returns to the apartment, where Grady assures him he won’t have any trouble finding a new love. Grady then kisses Homer on the lips. Homer jumps out a window and runs to Moe’s bar, desperate to forget the evening. He drinks so much that he ends up in a hospital with alcohol poisoning. When Homer regains consciousness, Dr. Hibbert shows him a videotape of Homer’s first bout with alcohol poisoning, which features a Young Marge telling an unconscious Homer they have a lifetime to work out their problems. Later, Homer tells Marge he never wants to be apart from her again.