Captain Underpants and the Sensational Saga of Sir Stinks-A-Lot is the twelfth and (possibly) final book in the Captain Underpants series, written and illustrated by Dav Pilkey. The book continues after the eleventh book, as George, Harold, and their clones switch places, but to find their gym teacher Mr. Meaner turning into Sir Stinks-A-Lot, who makes the students turn into slaves.
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