Story Synopsis: On a windy night during the last day of the month, a murder takes place in the Duke's residence, with Duke Zhou dying at the hands of a masked assassin. The assassination of the Duke angers the court, and the chief eunuch Sun Zhi conveys an imperial decree, giving the left supervisor of the censors, Fang Jin, a deadline to solve the case. Fang Jin delegates the investigation task to Tie Feihua, subtly expressing Sun Gonggong's suspicions regarding Tie Feihua's close ties to the Qicai Sect. With the Duke's death, it is natural for Sun Gonggong to suspect Tie Feihua, who therefore does not dare to neglect the matter. Tie Feihua secures the imperial sword and heads straight to Hangzhou to find the wealthy Yang Zhifeng. Tie Feihua remembers that not long ago, during an incident involving the eunuch Wang Jiangyang, the Fourth Master of the Qicai Sect, Shuang Feiyan, mentioned that the wealthy Yang Zhifeng might be linked to the sect's leader, Cheng Tong. Tie Feihua checks into the Yang residence, hoping to lie in wait. At night, a masked man brings a dart with a notice, explicitly stating that he will take Yang Zhifeng's life on the Dragon Boat Festival. Along with the notice, it is delivered to Hua E'rgou, a cook from the Yang residence. Hua E'rgou presents the notice to Yang Zhifeng to curry favor, taking the opportunity to redeem the servant girl Cai Ling on behalf of Yang Zhifeng's seventh wife, Lijun. Yang Zhifeng accepts the situation, and the ordinary person would not discern any flaws, but Tie Feihua detects a clue among them. In addition to Hua E'rgou, Yang Zhifeng's bodyguard Zhao Jiao and the account manager Mr. You are also suspicious.