A series of serial killings is exposed and creates a stir among the public. A killer called "Darker" has been leaving a death notification card after killing scumbags who evaded the law. To counter the provocation of the mysterious killer, the police creates a special investigation team.

• Guo Jingfei
• Gan Lu
• Li Qian
• Li Mincheng
• Jing Chao
• Wang Jing
• Su Bei Chen
• Liang Dawei