A snotty situation ensues when Melvin Sneedley, an academically gifted student, turns into the Bionic Booger Boy and must be stopped by George, Harold, and Captain Underpants.

George, Harold, Captain Underpants, and Sulu the bionic hamster battle the three ridiculous Robo-Boogers in an attempt to turn the Bionic Booger Boy back into Melvin Sneedly.

Principal Krupp once again turns into the superhero Captain Underpants in order to save the world, and Jerome Horwitz Elementary School, from the evil talking toilets and the Turbo Toilet 2000.

When George and Harold use their traveling purple potty to travel to another dimension where the school is nice and the principal, Mr. Krupp, thinks they're funny, they meet up with their evil twins and must face their cleverest enemies ever -- themselves.

"George and Harold have really done it this time--they've created a monster! She's faster, smarter, and more evil than anything the world has seen before--she's Wedgie Woman! With the help of her horrible robots and her horrendous hairdo, Wedgie Woman is on a mission to take over the world, and she'll give a whopping wedgie to anyone who stands in her way--including Captain Underpants."--P. [4] of cover.

After being sent to jail for the rest of their lives, George and Harold are taken on a trip back in time by Tippy Tinkletrousers back to their Kindergarten days where they must deal with their bully without the help of Captain Underpants.

A small mouse and his best friend, a giant flying robot, attempt to save the Earth when an evil Martian monkey and his mechanical creations attack. Includes brief "Flip-o-Rama" section that simulates animation and instructions for drawing six characters.

Petey the Cat is out of jail, and he has a brand-new lease on life his Petey's reevaluated what matters most, Li'l Petey is struggling to find the good in the world. Can Petey and Dog Man stop fighting like cats and dogs long enough to put their paws together and work as a team? They need each other now more than ever -- Li'l Petey (and the world) is counting on them!

Ricky Ricotta, his Mighty Robot, cousin Lucy, and some friends set out to save mousekind from Stupid Stinkbugs from Saturn, with a little help from some special gum and taffy.

Dog Man is down on his luck, Petey confronts his not so purr-fect past, and Grampa is up to no good. The world is spinning out of control as new villains spill into town. Everything seems dark and full of despair. But hope is not lost. Can the incredible power of love save the day?"--Publisher's description.