10,000 meters below sea level. On this Earth, there lies a world no one has yet to uncover.

The plot revolves around a summer vacation of Nobita and his friends under the waters of Pacific Ocean. Jaian and Suneo take Doraemon's underwater vehicle and travel through the Atlantic Ocean, trying to find a treasure ship. 
Along the way, they discover that the environment gun that Doraemon used to protect them is running out of energy leaving them vulnerable to the sea. Fortunately, they are rescued by some marine creatures. 
Doraemon and his friends are later captured by these creatures, revealed to be inhabinats of the underwater kingdom of Mu. It is revealed that another undersea kingdom, Atlantis, now controlled by robots, was about to destroy the Earth with nuclear weapons after mistaking a volcano eruption for an invasion. 
With the help of a young boy from Mu, Nobita and his friends attempt to stop the robots, but are all captured. However, when things are at their grimmest, Doraemon's robotic underwater vehicle sacrifices itself to destroy the computer that controlled all the robots and nuclear weapons. 
After returning to Mu, Doraemon and his friends are hailed as heroes. 
(Source: Wikipedia)

"Doraemon" is a series about a robotic cat named Doraemon, who travels back in time from the 22nd century to help a schoolboy named Nobita Nobi. Aside from the normal manga books, their great adventures to different places are specially described in Doraemon Long Stories books.

A new Doraemon series produced by the same team as the 1979 series (in association with Studio Pierrot) with new voice actors and staff and updated character designs.

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