Young troublemakers George and Harold are back with Mr. Krupp, the Jerome Horowitz Elementary principal they previously transformed into the superhero Captain Underpants with their 3-D hypno ring. This comic adventure begins in New Swissland, where everyone has a silly name. ("Just ask their president, the Honorable Chuckles Jingleberry McMonkeyburger Jr. or his lovely wife, Stinky.") New Swissland, just southeast of Greenland, is the home of the inventor of the Shrinky-Pig 2000 and the Goosy-Grow 4000--Professor Pippy P. Poopypants. When the professor decides to pitch his inventions in the United States, he is laughed out of every institution of higher learning because of his unusual name. Frustrated, he decides to become an elementary school science teacher where the innocent children will, he assumes, be accepting and loving. This is where his world collides with George and Harold's, who are not accepting of his funny name, but instead explode with laughter and promptly craft a new comic book called "Captain Underpants and the Pied Pooper of Piqua." This hilarious book will crack Pilkey fans up with tiny toilets of truth, evil gerbils, and even Cher's greatest hits. (The children--not notoriously good spellers--note: "All animal cruelty was simulated. No actual girbles were forsed to listen to Cher.") And what becomes of Professor Poopypants? He gets even, devising a method to convert all names into silly names. He creates a chart in which everyone has to use letters from their own first and last names to create a madcap moniker. In the end, George and Harold learn that it's not nice to make fun of people.