Back at the palace, Lingfu's mother begs the imperial highness of the city to help her find out what's wrong with her son. She's worried that he's dying, and she's also worried that the queen is trying to kill him. Lingfu is suffering from fetal toxicity, and the palace doctors can't figure out the cause. He's been carrying the toxin since birth, and his mother suspects that he was poisoned by the queen. The only thing that can save his son is a cure for the toxin, which is found in a hidden valley.