Bizarre serial murders suddenly broke out in the city, and each case left unexplained visions. Young police detective Yin Ran and his partner Li Kuoran were ordered to investigate. Together with psychological consultant Han Ke, freelance journalist Cheng Peiyao and mysterious man Song Weien, they secretly stirred up the trouble. They gradually discovered that all cases were related to the "Shadow Devour" incident many years ago. Due to the intertwining of multiple clues, various elements such as disappearances, suicides, cults, and mental hospitals are constantly emerging. Each story line has a unique main line and the terrifying truth under the night, but they gradually converge in the undercurrent. As the real murderer emerges and humanity collapses, the protagonists are involved in a restricted area beyond reality and inner demons, surviving on the border of the shadow, and finally facing all the truth - not only against the extreme terror of the outside world, but also at the critical point of redemption and destruction of their own souls.
