Click, click, click. That was the sound of military boots stepping on the metal floor. The rhythm was steady and unhurried. Zhou Chen held his breath and clenched his fingers tightly on the edge of the pipe. He could feel his heartbeat being amplified in this narrow space, and it sounded like a drum. Outside the vent is the maintenance passage on the second floor, and no one usually comes there. He chose this place because it was remote enough and no one knew how anyone would go this way. The footsteps stopped. Right below him!
