The limestone veins in the old industrial zone in the west of the city are deeply buried in the door light. Since 1967, the door light has generated piezoelectric pulses, allowing the bones of old workers to resonate and hear Qin Zhong's heartbeat a hundred years ago. Six generations of the Qin family have guarded the secrets of Wutong Lane. Qin Zheng inherited the dead line that can sense the door light, and he, Qin Yuan, Lao Lin and others investigated the residents who were exposed to radiation, and followed the list of 100 people left by Qin Jianguo. Everyone found chelating agents to relieve bone pain and gradually pieced together the past: Qin Jianguo distributed brown sugar water to record the victims, and Qin Su and Qin Yuan were involved in danger to block the underground B4 mirror door. Mirror doors, messengers, and dead people are three types of mirror-layer plague objects that rely on mirrors to move around. They are mirror images derived from archives. Qin Zheng, who is both a dead line and a live line, gathered six door lock codes, teamed up with Lin Jianguo, Xu Nian and others to go deep into the seven-story underground archives, archived fourteen epidemic objects, and solved the mystery left by Lin Yuan, who painted the door in 1937. He finally sealed the black door on the mezzanine, but found that there was a third unlocked door hidden underground. An archive secret that spanned a century has not yet ended.
