Captain Underpants: Big Bad Battle Part 2 by Dav Pilkey

Captain Underpants and the Big, Bad Battle of the Bionic Booger Boy, Part 2: The Revenge of the Ridiculous Robo-Boogers is the seventh book in Dav Pilkey’s Captain Underpants series, and it picks up right where Part 1 left off.

In Part 2, George and Harold (with a little help from Captain Underpants) face the chaos unleashed by Melvin’s botched transformation. This time, it’s not just one villain—they’re up against an army of disgusting, snot-fueled Robo-Boogers who follow their own slimy agenda. The story bounces between absurd slapstick, over-the-top gross-out humor, and plenty of flip-o-rama action, all leading to an outrageous resolution that only this series could pull off.

The tone stays true to Pilkey’s style: self-aware narration, kid-friendly rebellion against authority figures, and comic panels woven into the story. This book wraps up the two-part “Bionic Booger Boy” arc, bringing the Melvin storyline to a close… until the next ridiculous disaster.