When Nobita feels like diving in his hometown, Doraemon uses Underwater pompa Simulator (架空水面シミュレーター・ポンプ?) to pompa all the water to fill up water. That night, Doraemon and Nobita use a Diving Mask Simulator to dive underwater. Later on, lots of fish, and a squalo attack Doraemon and his friends. So, Doraemon puts a stop on the Underwater pompa Simulator, but there is a girl named Sophia, lay down on the bushes in his town.