The Qingchuan Mountains lie veiled in mist, concealing the secrets of a thousand-year-old town and the shadows left behind by the Republic of China era. A retired history teacher is found dead in a locked study. A button from a Republic-era military uniform and ink-stained scratches lead to a family secret cache and a dispute over cultural relics. A strange illness breaks out in a mountain town, and deadly toxins lurk in the water of a sacred spring. Behind it all lies a tunnel conspiracy pointing to the site of an armory. Detective Captain Lu Zeyan is called in at a moment of crisis. Through the rain and fog covering Qingchuan, he painstakingly pieces together the clues, from the ancient Gu family residence to an abandoned military camp, from the archaeology team's disappearance to the destruction of the Shadow organization. Every murder case is intertwined with old historical grievances and human greed. As long-buried secrets are revealed one by one, can justice pierce the fog and illuminate every dark corner of this land?
