The Crown Prince Li Chengqian is ambushed by a family disguised as Turks during a hunt, and Su Hao saves him from death. After returning to the palace, Su Hao intimidates the families in front of the emperor, killing their leader in the capital at night to establish authority for his sister, the Crown Princess. He also introduces papermaking, allowing the East Palace to gain financial power and prestige, and is granted a marquisate with fertile land. The families then manipulate Princess Wei, Li Tai, to instruct a palace maid to assassinate the pregnant Crown Princess. Princess Chengyang sacrifices herself to save her, causing the Crown Princess to go into premature labor, her life hanging by a thread. Su Hao vows in anger that if anything happens to his sister, he will take revenge on their enemies.