Lisa and Homer make a bet on who would win the 1948 presidential election, with Lisa betting Harry S. Truman and Homer going for Thomas Dewey. Lisa win and she has to choose the activity for Daddy-Daughter Day. Her activity is taking part in building homes for the homeless. When Homer paints a house, he takes off his wedding ring in order not to get paint on it, and Lindsay Naegle and Cookie Kwan mistake Homer for being a bachelor. Marge, driving by, sees Homer flexing for the women (though he is actually discussing the history of how Marge gave birth to Bart). She worries that Homer has no interest in her anymore, so she decides to get liposuction, on the advice of Manjula.
Unfortunately, a mix-up causes her to get breast implants. Marge's doctor says that she has 48 hours to live with her breasts until she makes a decision whether to keep them or not.
Meanwhile, Bart and Milhouse watch an old episode of Batman, featuring Krusty as a villain named Clownface, who threatens the Dynamic Duo with a rapidly spinning carousel of death. Bart and Milhouse like the idea, inspiring them to recreate the stunt, with Bart putting Milhouse on a roundabout in school. Otto starts the roundabout causing him to spin extremely fast with his bus, the roundabout to go flying through the air and knocking over the flag. Milhouse throws up on the flag while Iwo Jima veterans visit the school. Principal Skinner was about to blame Bart on this, and Bart says that he saw Krusty do the stunt on TV, and in response, Skinner leads a group protesting against Krusty, who is now seen as a dangerous influence to children.
At home, Marge tries to hug Maggie but she realises her breasts are making her life difficult. Homer, who comes home, sees Marge with her breast implants, and the family goes to dinner. The waiter, who had just rejected the Flanders said that there were no more seats but admits the Simpson family to a really good table after seeing her breast. The chef serves them real spaghetti, while Principal Skinner and his mother are eating some frozen canned spaghetti. Homer and several men start singing about Marge's breasts, and she meet a trade show executive, who gives her a modeling job. Marge prepares for the spot in the show, but her new appearance gives her problems when she is there. Bart recruits Krusty to win back his trust, using Milhouse and Stampy (Bart's old pet elephant) in a stunt, which of course goes out of control by stuffing Milhouse and Bart in his mouth. Homer tries to save them, but Stampy also puts him in his mouth. Krusty forgets the word that was supposed to make Stampy fall down and roll over. Things go horribly wrong, when the cops decide to shoot at Stampy, which would endanger Homer, Bart and Milhouse. To distract the cops, Marge takes off her dress and shows her breasts to everyone. Krusty, still hated by residents of Springfield, saves the day by uttering Stampy's safety word, Magumbo ("Look at those magumbos!") when he sees Marge's breasts, releasing Bart, Milhouse, and Homer.
The next day, the Springfield Shopper shows photos of Marge's breasts worth 25 pages, Krusty gets everybody's trust back and Marge decides to remove her implants, and everything goes back to normal.