When a sludge sickness pollutes the Corkuparipple Creek and Jo's brother, Geoffrey, becomes sick, action is needed to find a solution. Jo's dog, Bandaid, is missing, so Aunt Pepper organises for the search party to visit the Clam King under the Pacific Ocean.
Will the King have the answer to Bandaid's whereabouts? And will he be able to help heal Geoffrey and the environment?
A new mystery begins and Jo is faced with serious environmental issues full of sludge, snot and seawater.