The ant-like white-collar worker running in the urban forest accidentally got involved in a murder case in order to protect his beloved girl and became a suspect. The originally stagnant and mediocre life was broken in an instant. Under the dual pursuit of the police and the gang, the instinct for survival made human nature slowly ferment with a dangerous taste in the crisis. A former forensic doctor with a successful career and a happy family lost his wife and children overnight. In order to find his missing family, he searched alone for ten years, but finally chose to use a serial killing to find the answer for himself, even if the answer was cruel enough that he could not bear. The "bad policeman" who was irritable, extreme but smart was exiled by the secular world. In order to return to the police force, he must solve a mystery that no one can solve and let the evildoers pay for their sins. However, when the truth was in front of him, he could not prove his reasoning. Lies are covered by bigger lies, and sins are covered by deeper sins. After the darkness falls, the only thing that can illuminate the night is the faint light in the hearts of kind people.