In the twenty-fourth year of Kaiyuan, Chang'an was prosperous, but there was an undercurrent. General Zhang Mingming of the Zuo Jinwu Guard, together with his deputy Lu Lingfeng, teamed up with the forensic doctor "Fei Jishi" and the intelligence expert Chu Yingying to form an investigation team. They repeatedly solved strange cases: tribute tea poisoning, treasures hidden in ancient paintings, murders predicted in Buddhist temples, missing water transport... Behind each unit mystery, there is a shocking conspiracy of the "Tiandao Alliance".
This secret organization recruited old men from the previous dynasty, ambitious bureaucrats and strangers in the world, hoping to subvert the order of the prosperous Tang Dynasty. The team deals with the market and the court, not only to solve strange cases such as secret room murders and poisonous tricks, but also to deal with the court game between Li Linfu and Zhang Jiuling, and to balance the delicate struggle of the royal family. In the city of Chang'an, where Hu and Han cultures blend, Tang poetry, music and dance, and Zoroastrian secrets all become clues to the investigation, and the mystery of Zhang Mingming's life experience adds a fatalistic touch to this showdown between good and evil.
Crime and perseverance in the prosperous age, righteous choices in the whirlpool of intrigues, let's watch the detective team use their sword as an edge and wisdom as their edge to tear apart the conspiracy in the shadows and protect the last light of Chang'an.
