"Fat Man and Little Boy" is the fifth episode of the sixteenth season of the American animated television series The Simpsons. It originally aired on the Fox network in the United States on December 12, 2004. The episode was directed by Mike B. Anderson and written by Joel H. Cohen. Plot After losing his last baby tooth, Bart does not enjoy playing with his toys anymore and feels that he is maturing. To get out of his depression and express his emotions, Bart writes sarcastic and insulting phrases on his T-shirts. The shirts make him popular in town, and Bart sets up a stand in front of his house selling them. His business is shut down for not having a vending license, and he goes to a retailer's convention to obtain one. While leaving, he meets Goose Gladwell, a Willy Wonka-type salesman who sells joke products. Bart agrees to sell his shirts at Gladwell's store, making him the primary source of income in the family after Homer quits his job. Fearing that Bart has replaced him, Homer decides to nurture Lisa. They quickly bond, and Homer sees her entry for the science fair: a history of nuclear physics and a scale model of the first nuclear reactor. However, Martin shows them his project, a childlike robot. Homer helps Lisa ensure her project's victory by stealing plutonium from the power plant and using it to make her reactor fully operational. Meanwhile, Bart learns that Gladwell has sold the rights to the shirts under a contract that allows him to stop paying Bart. Homer stands up for Bart by threatening to detonate his nuclear reactor and destroy Gladwell's store. Gladwell accepts defeat, giving Bart and Homer all the money he has. As they leave, Bart thanks Homer for straightening things out. Cultural references The title of the episode references the atomic bombings of Hiroshima and Nagasaki: "Fat Man" is the name of the bomb dropped on Nagasaki, and "Little Boy" was the one dropped on Hiroshima. At the start of the episode, Lisa and Janey sing "Miss Susie." Bart finds that the Tooth Fairy has donated in his name to the United Way of America, rather than giving him a quarter. The toys that Bart disposes of are based on Spirograph, Etch A Sketch, Hungry Hungry Hippos, Monopoly, Parcheesi, Silly Putty, and Rock 'Em Sock 'Em Robots. He gives his toys a