Spring 1983

A century of bloodshed between warring star systems has plunged nearly 200 worlds into the flames of war. Now, an uneasy truce has settled across the Astragius Galaxy…

Chirico Cuvie, a special forces powered-armor pilot is suddenly transferred into a unit engaged in a secret and highly illegal mission to steal military secrets—from their own military! Now he’s on the run…from his own army!

Unsure of his loyalties and to cover their own tracks, Chirico is left behind to die in space. Surviving by luck, the renegade is now hunted by both the conspirators and military intelligence.

He is driven by the haunting image of a mysterious and beautiful woman—the objective of their mission, and his sole clue to unraveling their treacherous scheme. But the conspirators will do anything to preserve their mysterious agenda…

(Source: AnimeNfo)

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)