At the end of the Sui Dynasty in ancient China in early 600AD, the country is ruled by the inept Emperor Yang Di. The entire running of the court is thus passed on Yang Di's right-hand man Yang Su. To consolidate and strengthen his power, the vicious Yang Su builds an underground fortress where he harbours numerous assassins at his disposal, one of the most prominent ones being Hong Fu. Indignant at the country's deplorable state, a young man Li Jing arrives at the capital hoping to reverse the country's downward spiral. Hailing from a family which places patriotism and national welfare before personal safety, Li Jing's enthusiasm and prolific knowledge of martial arts and warfare places him in disfavour with Yang Su who views Li Jing a potential threat to himself. Yang Su promptly sends Hong Fu off to eliminate Li Jing.