During the Republic of China, a series of bizarre murders occurred in Peiping, and the deceased all showed the characteristics of monsters recorded in the ancient book "The Classic of Mountains and Seas". Folklorist Shen Jingyuan and retired military officer Gu Yelan, who have returned from studying abroad, discovered during the investigation that a lost book called "The Mountain and Sea Monster Book" was being used by others. Those legendary monsters were not fictions, but "demon-blooded ones" who really existed in the human bloodline. As the investigation deepens, they uncover a shocking secret that has lasted for three thousand years - there are seven demon-suppressing formations buried in the land of China. Once all are broken, the sleeping ancient demon gods will return to the world.
