The cover of the book 'Captain Underpants and the Big, Bad Battle of the Bionic Booger Boy, Part 1: The Night of the Nasty Noogies' by Dav Pilkey. The cover features the character Captain Underpants, a superhero alter ego of the main character, with a red cape and underwear, flying through the air with a big smile on his face. The background is filled with colorful illustrations of various characters and elements from the story, including a cityscape, a character in a blue shirt, and a character in a red shirt. The title of the book is prominently displayed at the top in large