After the incident of fox demon bewitching scholars subsided, the capital of the gods returned to its former prosperity and bustle. Empress Wu was in a good mood and decided to hold a grand autumn hunt, inviting princes, nobles and talented people who were good at martial arts to gather together to learn riding and shooting. Murong Ji, the young Khan of Tuyuhun, was also invited to participate in the autumn hunt, but by mistake became a "suspect" in a conspiracy to assassinate Empress Wu. Desperate Murong Ji had to ask Pei Kun for help, hoping that he could help find the real murderer and clear his grievances. In order to protect the peace and prosperity of the Tang Dynasty and to help his friends, Pei Kun and his partners Yuchi Zhu, Han Dongqing and others once again joined forces to investigate the case. There were constant dangers and jokes along the way, and finally the real murderer who tried to assassinate Empress Wu was found, preventing a war between the Tang Dynasty and Tuyuhun.