The Shen sisters are left all alone and destitute; the older sister is sickly and weak, while the younger sister is plain and ugly. After rescuing a three-tailed spirit fox, the fox cuts off one of its tails to repay the two sisters. Once impurities are cleansed and illnesses cured, the younger sister transforms her ugly face and is selected to enter the prince's mansion. However, she is unwilling to remain merely a maid. To make the spirit fox manifest its divine powers again, the two sisters repeatedly postpone the schedule for returning the fox to the mountain. As their greed grows stronger, the younger sister plans to cut open the fox immortal's inner elixir and swallow it alive in order to maintain eternal youth and keep her wealth and glory. All of this will provoke the wrath of the mountain god, and disaster will immediately descend.