In the early years of the Republic of China, the situation in Jiangcheng, Southwest China, was in chaos, and strange cases occurred frequently. Qin Huole, who had just returned from studying abroad, met the detective captain Song He in a chaotic world and joined hands to explore the mystery. With the help of female forensic doctor Fan Xiaofan, the three of them, with their sincerity and wisdom, dispelled the bloody fog that shrouded the people and protected justice in the world.