Five second-grade kids have earned a reputation as troublemakers at school, where strict Principal Brinway calls them the “Stinkers” for refusing to follow his rules. During a class trip to an aquarium, the group becomes convinced that Slappy, a sea lion, is unhappy in captivity. Determined to help, they set out to free him and get him back to the ocean, starting with a very unexpected stop in Brinway’s hot tub.