The monstrous Turbo Toilet 2000 is determined to take revenge on George, Harold, and Captain Underpants.

George and Harold have to figure out how to fix history in the tenth book in this #1 New York Times bestselling series by Dav Pilkey, the author and illustrator of Dog Man!

George and Harold have been turned into evil zombie nerds doomed to roam a devastated, postapocalyptic planet for all eternity! Unfortunately, the boys can't count on Captain Underpants for help because Tippy Tinkletrousers and his time-traveling hijinks prevented...

"George and Harold are fourth grade buddies who love practical jokes. When their latest prank drives their science teacher over the edge, their clueless principal, Mr. Krupp, quickly hires a replacement: Professor Pippy P. Poopypants. Of course, George and Harold can't resist making fun of the Professor's silly name. But then the Professor retaliates by forcing everyone in town to change their own names to be equally silly -- with colossal consequences!"--...

"Fourth graders George Beard and Harold Hutchins are a couple of class clowns. The only thing they enjoy more than playing practical jokes is creating their own comic books. And together they've created the greatest superhero in the history of their elementary school: Captain Underpants! His true identity is SO secret, even HE doesn't know who he is!"--

When George and Harold hypnotize their principal into thinking that he is the superhero Captain Underpants, he leads them to the lair of the nefarious Dr. Diaper.

The future of all humanity is at stake in the final color installment in this New York Times bestselling series by Dav Pilkey, the author and illustrator of Dog Man!

George and Harold, and their doubles, Yesterday George and Yesterday Harold, have a good thing going. Two of them go to school, while the other two hide in the tree house and play video games all day — then they switch! But it turns out there's something rotten...

Captain Underpants's spookiest--and stretchiest--adventure yet! George Beard and Harold Hutchins are back in a new Halloween adventure! Piqua's biggest pranksters are getting ready for the best holiday ever--Halloween, of course. But their dreams of costumes, candy, and haunted houses go down the drain when Mr. Krupp and Melvin start a campaign to make Halloween illegal! That's when George and Harold come up with HACK-A-WEEN, a totally legal spin-off...

George and Harold, and their doubles, Yesterday George and Yesterday Harold, have a good thing going. Two of them go to school, while the other two hide in the tree house and play video games all day--then they switch! But when their malicious gym teacher, Mr. Meaner, creates a method of mind control that turns their fellow students into attentive, obedient, perfect children, the future of all humanity will be in their hands!

The Turbo Toilet 2000 returns in the eleventh book in this #1 New York Times bestselling series by Dav Pilkey, the author and illustrator of Dog Man!

Just when you thought it was safe to flush, the Turbo Toilet 2000 strikes back! The carnivorous commode known for devouring everything in its path has built up a real appetite... for REVENGE! Luckily, the fate of humanity is once again in the hands of George and Harold and their annoying...

George and Harold's time-traveling Purple Potty lands them in a crazy place in the eighth book in this #1 New York Times bestselling series by Dav Pilkey, the author and illustrator of Dog Man! The teachers are nice, the cafeteria serves delicious food, and the school principal, Mr. Krupp, thinks George and Harold are hilarious. Something is very, very wrong -- and it gets even wronger when the boys' pet pterodactyl, Crackers, and Sulu the Bionic...