In Sinking, a giant wave overtakes the Mammoth Ferry on its maiden voyage, and all of the ship’s cargo is swept overboard! An enterprising young islander, Olive, watches her cousin, Troy, attempt to retrieve the sunken cargo and notices air bubbles rising to the surface around him. Olive uses these bubbles as a cue and, with the help of a visiting inventor, designs a vehicle called a submersible that allows them to sink to the ocean floor and then rise back to the surface. Before long, Olive retrieves the lost cargo and saves the day!