Captain Underpants and the Sensational Saga of Sir Stinks-A-Lot (Captain Underpants #12)

George and Harold and their doubles, Yesterday George and Yesterday Harold, have been taking turns going to school, but when the doubles fall prey to their gym teacher, Mr. Meaner, and his method of mind control that turns students into attentive, obedient, perfect children, it is up to original George and Harold to strike back.