Set during the Zhengde era of the Ming Dynasty, the film follows Zhu Dingcai, grandson of the late Prince Anhua, who was killed after a failed military plea to the emperor. Carrying a blood-written manifesto left by his family, Zhu risks everything to travel to the capital. Using a daring scheme known as "sacrificing oneself to trap the wolf," he successfully eliminates the corrupt eunuch Liu Jin. In recognition of his courage, the emperor grants him the title “Brave Junior Imperial Inspector,” sending him across the empire to investigate local grievances and uphold justice for the people.

Young chess prodigy Zhu Dingcai is on his way to the capital to petition the imperial court, accompanied by his protectors Gao Sheng and Wei Jingjing. When they arrive in Yulin, Shaanxi, they encounter a young man named Wen Tingjian, who is being mysteriously pursued by an assassin and urgently seeks their help. Kind-hearted and quick-witted, Zhu Dingcai uses strategic principles from Chinese chess—particularly the tactic of "resolving a kill and counterattacking"—to unravel a complex case involving a fierce dispute over business ownership rights.