Based on Ge Chuntao's short play "So It Was You." At a PLA barracks, during night patrol, sentry Sun Dagezi notices the kitchen light is on. He goes to check and finds cook Xiao Qian working frantically. After repeated persuasion from the squad leader, Xiao Qian finally leaves the kitchen. Once Xiao Qian is gone, the squad leader kneads the dough and then mends the comrades' rubber shoes. Shortly after, Xiao Qian quietly returns and turns off the light, forcing the squad leader to return to the dormitory. Thinking Xiao Qian is asleep, the squad leader writes a note asking him to fix the light after waking up, sets the alarm for 4:30, and goes to bed. Unbeknownst to him, Xiao Qian is actually imitating him by mending rubber shoes. Witnessing all this, Sun Dagezi goes to the kitchen and insists Xiao Qian return to the dormitory to rest. After finishing his shift, Dagezi heads to the kitchen to make steamed buns and prepare vegetable soup. When the squad leader and Xiao Qian wake up and go to the kitchen, they find the ready-made buns. Just as they start looking for the helper, Dagezi hurriedly turns off the light, leaving the three of them fumbling in the dark. As dawn gradually breaks, Dagezi is finally discovered by the squad leader and Xiao Qian.