Poor Stewart has a bad case of diarrhea, so the boys go to his house, and raid his food cupboards. Beavis discovers that if he eats too much sugar, he becomes his alter-ego, 'The Great Cornholio', and goes through the halls of Highland High School, annoying the students and staff.

Beavis and Butt-head are accused of stealing money from the Burger World cash register. The police give them polygraph tests to determine their guilt - and the boys try to cheat.