The trouble begins when Anastasia goes to the mailbox with two packages and her new dog, Sleuth. It's there that she accidentally puts the bag of dog droppings into the mailbox instead of her mother's package. When she realizes her mistake, Anastasia uses her school Values Class experience to help her decide what to do. But when the police take the corner mailbox, Anastasia's sure she's committed a crime that will land her in jail.