Captain Underpants and the Tyrannical Retaliation of the Turbo Toilet 2000
 Captain Underpants and the Tyrannical Retaliation of the Turbo Toilet 2000 is a graphic novel by Dav Pilkey and a second spin-off of Captain Underpants.The plot of the book involves George and Harold the lead characters from Pilkey's Captain Underpants series complaining that scientists don't know everything so they make a comic book about science facts.