An American teenager who is obsessed with Hong Kong cinema and kung-fu classics makes an extraordinary discovery in a Chinatown pawnshop: the legendary stick weapon of the Chinese sage and warrior, the Monkey King. With the lost relic in hand, the teenager unexpectedly finds himself travelling back to ancient China to join a crew of warriors from martial arts lore on a dangerous quest to free the imprisoned Monkey King.

In his youth, Li Bai witnessed the tragic Battle of Broken Leaf City, embarked on the path of seeking fair power with the teachings of an old master who saved the world and his teacher Pei Yi. Entering Chang'an for the first time, with no ambitions and pity, Li Bai, who was recommended by Anxi Dufu to enter the government with poetry and literary talent, turned out to be a night marcher to fight against evildoers. Unexpectedly, the conspiracy of blood and rain is waiting in the dark, and the mystery in the alchemy is so heavy. Can the sleeping Chang'an be saved from danger? Can Li Bai grow up to be a real hero in the fight against the bandits?