Mr. and Mrs. Twit are the smelliest, nastiest, ugliest people in the world. They hate everything-except playing mean jokes on each other, catching innocent 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. They don't just want out, they want revenge. The misadventures of two terrible old people who enjoy playing nasty tricks and are finally outwitted by a family of monkeys.