Living in seclusion for ten years, the Unusual Affairs Bureau asks me to come out of retirement to hunt giant beasts. Xiao Lieyun, heir to the hunting school, experienced the destruction of his sect ten years ago firsthand, living in seclusion in the Qilian Mountains and staying out of worldly affairs. An Unusual Affairs Bureau team encountered a giant unusual beast in Mount Shennong, and the entire army was wiped out, so they paid a huge sum to ask him to come out of retirement to hunt the beast. Xiao Lieyun, carrying the spiritual white wolf Ashui, goes deep into the primitive mountain forests with agent Wang Bingqian and retired soldier Yu Lei to uncover the secret of the giant snake Zhuyin, only to realize that the tragic case of ten years ago was not a natural disaster, but a conspiracy by the hunting school traitor Qin Wujiu. Qin Wujiu controls unusual beasts with the heart-controlling Gu, attempting to awaken the egg of the god of Kunlun Ruins. As the group breaks into the ancient village of Shennong and goes deep into Kunlun Ruins, Xiao Lieyun bears the ancestral lethal weapon Underworld Fire Thin Sky, vowing to take revenge for his sect and relatives.