Mo Fan is presumed dead, yet rumors of his location prompt childhood friend Zhang Xiaohou to search for him. When they reunite, Mo Fan convinces Zhang and Li Man to kill a giant lizard whose spirit will help him heal from the side effects of his demonic powers.
Mo Fan spends time with stepsister Ye Xinxia in Song City and witnesses a serpent towering over the skyline. He asks teacher Tang Yue about it; she takes him to her island home and shares her history with the beast. In return for its shed skin, Mo Fan agrees to protect it.
Meanwhile, a White Eagle demon attacks the western fortress while an epidemic spreads from Bai City to Song City. The giant serpent is blamed for the outbreak; determined to prove its innocence, Mo Fan searches for the real source of the disease and a cure.
