Taking place in ancient China's Qin Dynasty, a valiant assassin endeavors to assassinate the Emperor in order to protect his homeland. Despite his best efforts, the assassin fails, prompting the Emperor to order his troops to execute the assassin's eight-year-old son. Fortunately, a skilled swordsman steps in and saves the boy. After eluding the Emperor's forces, the swordsman and the boy embark on a quest to alter the fate of the empire. Along their journey, they encounter both allies and adversaries.