The film is based an episode from the Chinese mythological novel Apotheosis of Heroes.
The story opens with a powerful general by the name of Chentang Pass. A beautiful boy-child springs out from a ball of flesh shaped like a lotus bud.
The Great Monad comes to offer his congratulations. He takes him as a disciple and names him Nezha. He then gives him two magic weapons:the Firmament Ring and the Armillary Sash.
One day when Nezha is seven years old he goes to the nearby seashore for a swim. There he encounters a patrolling Yasha demon, stealing children to feed the Dragon King. Nezha wounds the Yasha demon and saved a little girl from its clutches. In a rage, the Dragon King sends his third son to capture Nezha. But killed instead. Now completely infuriated, the Dragon King hitches up with the dragon kings of other seas and unleashes a raging storm, wreaking havoc on Chentang Pass. Not wanting to involve others in any further misery, Nezha commits suicide...