backfires in the second book in this #1 New York Times bestselling series by Dav Pilkey, the author and illustrator of Dog Man!

George and Harold are usually responsible kids -- whenever anything bad happens, George and Harold are usually responsible! This time, they accidentally invent an army of terrifying talking toilets. Luckily, they know a superhero with enough snap in his waistband to save the day! This looks like another job for the amazing Captain Underpants!