As Homer, Lisa, and her friends watch the announcement of the year's Nobel Prize winners, they are astounded to hear that Krusty the Clown has won the Peace Prize. Krusty picks Homer to accompany him to Oslo for the awards ceremony, and Homer decides to take Bart with him. Their plane lands in The Hague, and it is revealed that the Peace Prize announcement was a ruse to bring Krusty there so he could be tried by the International Court of Justice for his deplorable public behavior over the years, such as dropping a monkey from the Eiffel Tower in Paris, and stealing the act from a local clown in The Hague. Homer and Bart search desperately for any evidence to show that Krusty has made a genuine contribution to humanity, and eventually argue that his refusal to perform at Sun City because he wanted potato chips led directly to the South African government's decision to release Nelson Mandela from prison. Even though it is obvious that these two incidents are not connected in any way, the court accepts this argument and frees Krusty, who immediately seeks out the nearest place to buy marijuana — the courthouse cafeteria.
Meanwhile, Marge surprises Lisa by sending her to a performing arts camp for a week. She eagerly immerses herself there in music and theater, meeting several campers who love to break into song and two guitar-playing hipster counselors, Ethan and Kurt. When Marge takes her home at the end of the week, Lisa has trouble readjusting to normal life and looks for a chance to express her newly awakened creative side. She runs away from home and seeks out Ethan and Kurt in "Sprooklyn", described by the counselors as the "artistic hotbed of Springfield". However, she soon learns that they have grossly exaggerated the area, which is really a run-down slum, and that they actually work at a sandwich shop. They sing a song about the difficulties of being an artist, during which Krusty gets beaten up for accidentally announcing he is the prison snitch. Ethan and Kurt encourage her to return to her family and think about trying to make an artistic name for herself when she is older. As Marge arrives to take Lisa home, Ethan and Kurt show off a mural that they have painted in her honor, which takes up an entire side of a building.