This book is set in the turbulent Shenlong period after Wu Zetian abdicated. Di Renjie and his team traveled across the Western Regions and the Central Plains to solve the puzzle of the Silk Road. From the Dunhuang murals to the secret passages of Gaochang, from the Luoyang murder case to the Tingzhou conspiracy, each case is deeply rooted in the soil of the multi-ethnic blending of the Tang Dynasty, intertwined with the struggle for power in the court and hidden dangers at the border. The work inherits the essence of classical public cases, emphasizes original reasoning and portrayal of human nature, and weaves a strange and magnificent picture of the dark side of the prosperous times in the gaps of history.