In a mystical Chinese landscape, a powerful sorcerer named Abbot Fahai dedicates his life to battling evil spirits and protecting humanity. One day, a snake demon named Susu takes the form of a beautiful woman and encounters a kind-hearted herbalist named Xu Xian. The two quickly fall in love, unaware of each other's true nature. Their bond grows stronger, but their relationship inadvertently disrupts the balance between the human and spirit worlds, drawing the attention of Fahai. As the sorcerer senses the disturbance, he sets out to investigate the situation, believing that Susu's presence poses a grave threat to humanity.

Meanwhile, Susu is unaware that her sister, who is also a snake demon, does not approve of the burgeoning love affair and worries about the potential ramifications. Fahai's apprentices aid him in tracking down Susu, leading to multiple confrontations filled with supernatural battles. Xu Xian, caught between his love for Susu and his loyalty to his fellow humans, struggles to understand the calamity unfolding around him. The story progresses with intensifying stakes, as Fahai seeks to uphold his duty, Susu fights to protect her love, and Xu Xian grapples with the revelations that shake his world.