During the Chenghua period of the Ming Dynasty, the government was corrupt and evil prevailed. The West Factory and the East Factory were controlled by eunuchs, who confused right and wrong, framed loyal officials, and silenced the government and the people. From time to time, exiled swordsmen such as Zhao Huaian (played by Jet Li) stepped forward and successively eliminated several treacherous officials in the East Factory, causing the eunuchs to tremble with fear. At this time, the powerful West Factory Supervisor Yu Huatian (played by Chen Kun) intervened. On the other hand, the palace maid Su Huirong (played by Fan Xiaoxuan) was pregnant and fled for her life. She was chased by Yu Huatian's minions and was fortunately rescued by the mysterious knight Ling Yanqiu (played by Zhou Xun). The two fled all the way to the outside of the pass and came to the Longmen Inn, which had caused a bloody storm. Longmen Inn is as dangerous as before. Yu Huatian's men chased here and were on the verge of a war with the Tatar caravan that had arrived earlier. At a critical moment, Bu Cangzhou (played by Chen Kun) and the female knight Gu Shaotang (played by Li Yuchun), who looked very similar to Yu Huatian, stayed at the inn. Soon, Zhao Huaian and his group also sneaked into Longmen. Various forces gathered here, a new battle between good and evil is about to begin, and a huge secret is about to be revealed...