Mr. and Mrs. Twit are the smelliest, nastiest, ugliest people in the world. They hate everything-except playing mean jokes on each other, catching unsuspecting birds to put in their bird pies, and making their caged monkeys, the Muggle-Wumps, stand on their heads all day. But the Muggle-Wumps have had enough. With the help of Roly-Poly Bird, they set out to get some well-deserved revenge.