Chen Du traveled to the Zhenguan year of the Tang Dynasty and rescued Du Xuanling, a charcoal seller who was besieged by bandits. The old man tore open his rags and revealed the iron certificate of the alchemy book, which turned out to be a retired veteran given by the late emperor. Chen Du was forced to get involved in the secret war between the old nobles and the imperial court. He teamed up with Du Xuanling to train local heroes, but this led to the pursuit of Pei Zhao, the young minister of Dali Temple, the wooing of Wu King Li Ke, and the counterattack of Ashina Dubi, the Turkic prince.
