Shouxue must solve the mystery of the ghost that appears beneath the willow tree, and the two ghosts that appear in the emperor's chambers.

Yi Siha, a eunuch serving Feiyan Palace, visits Ye Ming Palace. He has seen the ghost of a boy holding a blue swallow feather and asks Shouxue to help him. During her investigation, Shouxue comes across Yi Siha being caned by some older eunuchs. When she stops the punishment, Yi Siha's mentor Kang Lan trembles with fear. In Shouxue's eyes he saw a horrifying monster.

Court lady An Huilan comes to make a request. She claims she can hear the voice of a dead consort coming from within the water. Xi Wanlin, the Magpie Consort during Yandi's reign, drowned herself in the lake on the day the emperor was to visit her. The voice within the water is allegedly hers. Huilan asks Shouxue to save Wanlin, but Shouxue realizes there is more to the story than what Huilan is telling her.