Mo Fan is presumed dead. Nonetheless, hearing rumors about his whereabouts, Mo Fan's childhood friend Zhang Xiaohou sets out to find him. Upon reuniting, Mo Fan enlists Zhang Xiaohou and Li Man to kill a giant lizard whose soul will help him recover from the side effects of his devil powers.

Human once more, Mo Fan spends time with his stepsister Ye Xinxia in Song City, where he witnesses a giant snake towering over the buildings. When Mo Fan asks his teacher Tang Yue about the snake, she takes him to her island home and shares her history with the beast. Mo Fan agrees to help her protect the snake in exchange for its valuable shed skin.

Meanwhile, the White Eagle demon attacks the Western fortress and a plague spreads from Bai City to Song City. As blame falls on the giant snake, Mo Fan is fully determined to prove its innocence by searching for the true source of the disease as well as an antidote.