Bottom-layer little Taoist priest Li Ping'an takes shelter from wind and rain in a ruined temple, encountering a man-eating wolf demon. On the verge of dying in battle, he awakens the mysterious supreme treasure Heaven and Earth Exorcism Illustrated Catalog, directly gaining sixty years of Taoist cultivation and lightning magic divine powers. He takes action to exterminate the demon, only to horrifyingly discover afterward that the wolf demon is actually an official on the payroll of the Dayong Exorcism Bureau. Killing an official is equivalent to treason, and catastrophe is imminent. He flees in a panic, passing a shady inn where he exposes the conspiracy of a painted-skin demon and an evil cultivator, seizing evidence of the Exorcism Bureau colluding with demons and monsters. To escape the imperial court's inescapable net, Li Ping'an coerces the local goblin Huang Laosan to lead the way, stepping into the perilous Dead Man's Gulch, fleeing for his life while confronting the dark truth of human-demon collusion behind troubled times.