On the eve of the Shangyuan Lantern Festival in the prosperous Tang Dynasty, the servant of the East Palace died mysteriously in the secret room, and the death pattern echoed the old case ten years ago. {Shen Yan}, the former head catcher of the Jingzhao Prefecture who lived in seclusion in Chang'an and opened a wine shop, was forced to come out by the Jingzhao Prefecture because he was once the disciple of the chief prosecutor of an old case. During the investigation, he discovered that half of the jade pendant held by the deceased was actually related to his sister Shen Li, who had been missing for many years. The clue leads directly to the palace of the powerful Princess Taiping. While avoiding the killer sent by the princess, Shen Yan unites with the survivors of the old case to deal with Chang'anfang City and the palace wall. The light of the sword reflects the moon in Chang'an, and the truth is hidden in the fog of intrigue. He will eventually uncover the conspiracy of the prince's struggle behind the two murder cases, and find his lost sister in the bloody storm.
