When Arthur catches Buster sucking his thumb, Buster worries that Arthur will tell the entire school. Can Arthur stay mum? Or is this secret just too juicy not to share? Tired of doing chores, Arthur and the gang decide to invent their own country: Kidonia. But when there are no rules, no laws, and no chores, someone's bound to ruffle a few feathers. Will this kid-ruled utopia flourish or descend into anarchy?