Bart and Milhouse make their way to the Android’s Dungeon, where Comic Book Guy subjects them to various humiliations… until he realizes he has competition from a new comic book store across the street called Coolsville. Bart and his friends check out the store, where they’re treated like royalty by a friendly guy in a porkpie hat named Milo. Lisa marvels at the store’s inventory, which includes adventure comics like Tintin and Asterix. Coolsville attracts some real-life comic book creators, such as Alan Moore, Art Spiegelman, and Dan Clowes. Comic Book Guy attempts to win back customers by announcing that he’s now selling ninja weapons. When that fails, Comic Book Guy starts hacking up Coolsville with a sword. Moore, Spiegelman, and Clowes respond by attacking Comic Book Guy. Marge realizes her middle-aged body could use some help. She decides to join a gym, but the glamorous facility is tailored to young, energetic types. This gives Marge an idea. She decides to start a gym for “regular ladies.” When she sees a “for rent” sign in Comic Book Guy’s window, she thinks it will make the perfect place for a gym. Marge’s gym, called Shapes, is an instant success: middle-aged women pour through the door.

Marge’s gym is so successful that she needs to open a second store. Before long the business lands her on the cover of several magazines, and she even makes an appearance on “The Opal Show.” Homer accompanies Marge on a business trip to Palm Springfield. There he rubs elbows with the trophy second-husbands of successful women. They warn him that sooner or later Marge will dump him, and hook up with a younger, fitter guy. Before long Homer begins to fear that the men he met on the trip are right: Marge begins to show telltale signs that she’ll dump him. Homer begs the trophy second-husbands for help. One of them pulls Homer aside. He tells Homer that he’s really a first husband. He used to be dumpy and fat; but then he got smart, and turned himself around by exercising and losing weight. Homer interprets this in his own way: he decides to get his stomach stapled.

Homer consults a plastic surgeon about gastric bypass surgery. Dr. Velimirovic warns that such a procedure should be considered only as a last resort. Despite this, Homer goes through with it. When he returns home, Lisa notices a difference in his eating habits. Though the operation was done in secret, Homer tells the kids he did it so Marge would find him more attractive. When Marge returns home, she’s pleased to discover that Homer has turned their bedroom into a romantic lair. Unbeknownst to Marge, Homer has hidden all his extra skin (from when he was fat) with the help of a “chip clip.” Marge loves Homer’s new look, but Homer can’t stand the fact that he’s being forced to hide all his loose skin. He returns to the doctor’s office, where Velimirovic agrees to perform additional plastic surgery that will make Homer look better. Homer is taken to the operating room, where an anesthesiologist puts him to sleep. When the procedure is over, Homer makes his way to Shapes, where he shows off his new body. Onlookers are horrified, and begin chanting “monster.” The angry mob chases Homer and Marge through the streets. Like a scene out of The Hunchback of Notre Dame, Homer carries Marge into the bell tower of a cathedral. There Marge tells Homer that she’s become too successful to stay married to him. She then pushes him off the bell tower. Homer screams as he falls… only to wake up in a surgery recovery room. He realizes the plastic surgery was all a dream. Marge tells Homer she told the doctor not to go through with the procedures, but she did give him permission to un-staple Homer’s stomach. Later Marge’s newest business venture, a gym for middle-aged married men, turns into a failure.