During the Tang Dynasty's Chuigong era, Di Renjie grows disillusioned with Empress Wu's willingness to sacrifice innocent lives for ambition. He and his companions leave the divine capital to inspect the Jiangnan region, only to discover that beneath the façade of a flourishing golden age, demons and sinister forces seem to roam unchecked. Amid ruthless power struggles, insatiable greed, and madness born from obsession, Di Renjie is drawn into a series of intricately woven conspiracies. With strange cases unfolding before him and truth obscured by layers of deception, the legendary detective of the Great Tang relies on an almost supernatural intellect to uncover the smallest clues and peer deep into the human heart.