Captain Underpants and the preposterous plight of the Purple Potty People / the eighth epic novel by Dav Pilkey ; with color by Jose Garibaldi and Corey Barba.
Harold and George's time-traveling Purple Potty lands them in an alternate universe where everything seems delightful, but evil lurks just beneath the surface, and leads to a battle between Captain Underpants and his own evil twin.