Lao Lin is over 40 and still a single father. It is self-evident that he is depressed and different from ordinary people. What is more special is his profession - the people's police. As a policeman, he is naturally dedicated and concerned about the people. His phone is not turned off 24 hours a day, and almost all the residents in the area have his number. He is undeterred by big and small things. Lao Lin and Director Yu Jia have been good colleagues for many years. If Liu Xiaoxiao had not pursued Lao Lin crazily, neither of them would realize that they have developed a tacit understanding and feelings between men and women outside of work for so many years. But even if they realized it, due to face and public opinion, neither of them was willing to break this window paper first. Just when he was anxious, Lao Lin received a razor blade and a dead mouse sent by the murderer. As an old policeman who has experienced ups and downs, he is not afraid of death, but he is afraid that the people he loves will be implicated. Protect the people while also protecting your family and friends. Lao Lin and his colleagues at the police station face the challenges from criminals together.