In the mystical Taihang Mountains, where magic flows and powerful yao roam, Hongjun has grown up sheltered from the human world. A half-yao himself, he’s never had reason to leave - until the mountain’s ruler sends him on a dangerous mission: hide his true nature and join the Great Tang Department of Demonic Exorcism in Chang’an. Upon arriving in the bustling capital, Hongjun meets Li Jinglong, a luckless soldier with no spiritual power tasked with leading a team of extraordinary exorcists.

Together, they and their enigmatic companions must face the dark forces threatening the city. But as a bond begins to bloom between Hongjun and Li Jinglong, Hongjun wonders: Can he trust Li Jinglong with the truth of who - and what - he is?