In Chang'an during the prosperous Tang Dynasty, an old water transport case suddenly broke out. Su Wan, a poor girl from a poor family, is the daughter of a widower. With her superb autopsy skills and calm judgment, she is introduced to Dali Temple by Pei Yanzhi, the young minister of Dali Temple. The two teamed up and solved one after another: the case of serial murderers in the ghost market, the case of the serial disappearance of courtesan, the case of the unjust students of the Imperial College, the Chang'an epidemic poisoning case, and the case of the Royal Cemetery Poison Bureau. All the cases pointed to a powerful figure... Su Wan was hunted down, framed, and seriously injured, and finally discovered that there were two invisible hands behind the scenes. In the end, Su Wan risked her life to uncover the truth... And became the first female minister of Dali Temple in the Tang Dynasty.
