In the prosperous and picturesque water town of Jiangnan, bizarre murders occurred one after another in the famous building "Yanyu Tower", and the seemingly peaceful undercurrents of the rivers and lakes surged. Traveling doctor Su Yebai, a young man who appears to be careless and unruly but is actually thoughtful and possesses unique skills, is involved in this complicated and confusing unsolved case by chance. As the investigation deepens, he not only has to battle wits with the cunning real murderer, but also uncovers a huge conspiracy hidden behind the murder that has lasted for decades and involved many forces - a shocking secret about the ancient martial arts secret book "Secret Records of Qingming" and the great catastrophe in the world.
