Lin Lan and Lin Yuan Hao, prosecutors from the Criminal Procuratorate of the Jianghai City People, were appointed to form a team. They use advanced techniques to break the bottleneck of "zero confession" cases that are difficult to solve.

In 1931, after Gu Shunzhang’s betrayal, undercover agent Qian Zhuangfei races against time to deliver critical intelligence, while Li Kenong, Hu Di, and the “Three Dragons” work together in a daring mission to protect the Party’s Central Committee.