The film mainly tells the story of ordinary high school student Lu Fan who was accidentally involved in the demon battle, and was awarded the top master of the immortal world. He was then forced to take the story of “Xianxia College” to cultivate immortality, love, counterattack and destroy the Mozu.

In the early years of the Republic He Changsheng followed his grandfather around the world and learned a lot about medicine. One day, while He and Hu are tending to the shop, a woman dressed as a Miao, Ah Man, comes to the door and asks He Changsheng to pay his father's debt to his son and fulfil his promise.

In the flourishing Yin Dynasty, several mystical murder cases by fire occur in Daye, the capital. All of them are strange, terrifying, and mysterious. Shi Hao Xuan from Tianzhao Prefecture and Xuan Kun of the City God Temple get involved to find out the truth. Solving the enigmas, they discover the truth about the Fire Case of 20 years ago that exterminate the whole family, while a secret file reveals their identities. A series of delicately planned conspiracies are unveiled amidst hatred and ambitions.