There is a murderer hiding in the community. The real estate agent informed everyone in the group to immediately close the door and wait for the police to arrest him before going out. After a while, the group informed that the murderer had been captured. At this time there was a knock on the door. I looked through the peephole and saw it was the police. Comrade, please open the door for routine inspection. Just when I was confidently unlocking the anti-theft lock and preparing to open the door, a barrage suddenly flashed in my mind. Stupid! The murderer was wearing a police uniform and tricking people into opening doors. This was already the seventh household he had killed!