Although the Department of Exorcism has successfully thwarted the fox yao's attempts to infiltrate the imperial examinations, Hongjun, Li Jinglong, and their companions are no closer to uncovering the identity of the yao king of Chang'an. Investigations stall until the group stumbles across a series of bloody murders in the capital.

What appears to be a gruesome coincidence soon points to a larger plot as Hongjun and Li Jinglong discover evidence of yao involvement. Yet as the clues pile up, the group fears their enemies' goals go far beyond murder: They may have their sights set on the emperor himself. Hongjun and Li Jinglong's growing bond is tested as the fate of the empire--and their very lives--are put on the line in the hunt for the mastermind lurking in the city's shadows.