Synopsis：A suspenseful detective movie directed by Guo Yulong and starring Zhu Zixiao. When the "ghost ship" entered Hong Kong, the boss wanted to close the case with "Water Bandit Rebellion" in order to protect Mingzhe's safety, but Di Renjie faintly felt that something was wrong. The grand ceremony is just around the corner, and people in Chang'an are panic-stricken. The empress ordered Shen Ming, the head of the Dali Temple, to close the case within three days. Shen Ming had no choice but to put the pressure on Di Renjie to solve the case. Leng Jiyue, the chief of the water supervision department, also joined in, and met Duan Yan, an old acquaintance, on the "ghost ship" where the incident occurred. The three went to the "Xiacheng" of Chang'an Intelligence Center to obtain information. After exploring all the way, the two underground forces in Chang'an finally found the place where the secret is hidden--the cloud cave.