Guo Yu, was one of the ant tribe, dedicating to his work in the city. In order to protect his beloved girl, he is inexplicably involved into a murder case. His life is totally ruined and he, himself is also changing. And Luo Wen, a successful medical examiner, lost his whole family all of a sudden. He has been searching for ten years but in the end, he chooses to be a serial killer to find the answer, although that is not what he wants.