Captain Underpants and the Revolting Revenge of the Radioactive Robo-Boxers (Captain Underpants #10) (10)

When we last saw our heroes, George and Harold, they had been turned into evil zombie nerds doomed to roam a devastated, postapocalyptic planet for all eternity. But why, you might ask, didn't the amazing Captain Underpants save the boys from this frightening fate? Because Tippy Tinkletrousers and his time-traveling hijinks prevented George and Harold from creating Captain Underpants in the first place! Now, having changed the course of human history forever, they'll have to figure out a way to CHANGE IT BACK!

• Captain Underpants and the Terrifying Return of Tippy Tinkletrousers (Captain Underpants #9)
• Captain Underpants and the Tyrannical Retaliation of the Turbo Toilet 2000 (Captain Underpants #11)
• Captain Underpants and the Sensational Saga of Sir Stinks-A-Lot (Captain Underpants #12)
• Captain Underpants And The Preposterous Plight Of The Purple Potty People
• Captain Underpants and the Big, Bad Battle of the Bionic Booger Boy, Part 2: The Revenge of the Ridiculous Robo-Boogers (Captain Underpants #7): Color Edition
• Captain Underpants and the Big, Bad Battle of the Bionic Booger Boy, Part 1: The Night of the Nasty Nostril Nuggets (Captain Underpants #6)
• Captain Underpants and the Preposterous Plight of the Purple Potty People: Color Edition (Captain Underpants #8)
• Captain Underpants and the Big, Bad Battle of the Bionic Booger Boy, Part 2: The Revenge of the Ridiculous Robo-Boogers
• Captain Underpants and the Wrath of the Wicked Wedgie Woman: Color Edition (Captain Underpants #5)
• Captain Underpants and the Perilous Plot of Professor Poopypants: Color Edition (Captain Underpants #4)