comic George and Harold wrote. Soon, Evil George and Evil Harold find the treehouse, rummage through it and find the "Goosy-Grow 4000", which they use to transform Sulu into a giant monster. Sulu charges at George and Harold, but Crackers flies in and carries George and Harold away while Sulu attacks the city and Evil George, Evil Harold, and Captain Blunderpants rob a bank. When George and Harold try to drink the Extra-Strength Super Power Juice, they discover it is empty, despite there being a third of juice earlier. George explains that there is only one plan left they can resort to now. They go to Mr. Krupp's house (which George and Harold covered in toilet paper at an earlier point) and knock on his door. Right after Mr. Krupp answers, George and Harold quickly snap their fingers and Mr. Krupp turns into Captain Underpants, who then defeats Sulu. Evil George, Evil Harold, and Captain Blunderpants return from robbing the bank, and order Captain Blunderpants to fight Captain underpants, but George snaps his finger and turns Captain Blunderpants back into Nice Mr. Krupp, having learned how to do so from the double's comic. Captain Underpants ties the alternate counterparts up, but when Harold states that nothing can go wrong, George warns him that it isn't nice to say things like that, and then a rainstorm suddenly hits and turns Nice Mr. Krupp back into Captain Blunderpants and Captain Underpants back into Mr. Krupp. George and Harold try snapping their fingers, but the rain is pouring too hard on them. Mr. Krupp can't figure out how he got outside, so he goes back to his soggy toilet paper-covered home to get back to bed while Captain Blunderpants frees himself and Evil George and Evil Harold. George and Harold fly away on Crackers while the doubles pursue them. After arriving at the Treehouse, George finds the Shrinky-Pig 2000, which they could use to shrink their counterparts. Unfortunately, it is too late as Captain Blunderpants grabs the two by their Shirts while the Shrinky-Pig 2000 is taken by Evil George and Evil Harold. Before Captain Blunderpants can finish off George and Harold, George and Harold's grandparents arrive and order Captain Blunderpants to put down their grandchildren, but he refuses, causing George and Harold's grandparents to transform into Boxer Boy and Great-Granny Girdle (having been inspired by George and Harold's comic). They then battle