Allen enjoyed the smart life in the penthouse apartment of Emerald Court until late one night. The entire building suddenly lost power and internet, and the access control system was completely locked. He received a text message from an unknown number: "The game begins. The first rule: keep quiet." Slow and regular footsteps sounded outside the door, like a death knell in the dead silence. Allen frantically called for help, but only heard a busy signal. When he approached the cat's eye tremblingly, he only saw a blur of dark blue - that was the color of the cleaner's uniform.
