The film starts with Gian seeing some like spirit and it asks him to accomplish a task. The story starts when a stray dogs are searching some foods in the can. Then a dirty white dog comes out of nowhere. Just then, the dog creates a close stare to the stray dogs and forces to run away. But the dog is disappointed that he doesn't know what to do after searching the garbage, under the pouring rain. After that, Suneo starts saying about the discoverable places on Earth and him and Gian are totally disappointed about that. That then, they are asking favor to Nobita to take them to an undiscovered place to be seen by their naked eyes. Nobita refuses but tells he will try his best. He comes to upstairs to explain Doraemon what the problem is now.

When Nobita feels like diving in his hometown, Doraemon uses a Underwater Pump Simulator to pump all the water out of Tokyo, causing the entire city to go underwater. That night, Doraemon and Nobita use a Diving Mask Simulator to dive underwater. Later on, lots of fish, and a shark attack Doraemon and Nobita. So, Doraemon puts a stop on the Underwater Pump Simulator, but there is a girl named Sophia, lying down on the bushes in his neighborhood.

Doraemon and friends trying to save a boy name Kukuru and his tribe from Gigazombie who want to change history for his own sake in the ancient times.

In the suburbs of Tokyo some time ago, there lived a clumsy boy about 10 years old. There appeared in front of him named Sewashi, Nobita's descendant of four generations later from the 22nd century, and Doraemon, a 22nd century cat-type caretaker robot who helps people with its secret gadgets. Sewashi claims that his family is suffering from the debts Nobita made even to his generation, so in order to change this disastrous future, he brought along Doraemon as Nobita's caretaker to bring happiness to his future, although Doraemon is not happy about this. And so Sewashi installed an accomplishment program into Doraemon forcing him to take care of Nobita. Unless he makes Nobita happy, Doraemon can no longer go back to the 22nd century. This is how the life of Doraemon and Nobita begins. Will Doraemon succeed this mission and return to the 22nd century? Written by VoGuy