- During Emperor Renzong's reign in the Song Dynasty, Bao Zheng (Shaun Tam) is appointed Kaifeng Prefecture Prefect. Bao Zheng, his trusted aide Gongsun Ce (Raymond Cho), Guard Zhan Zhao and the four Constables are determined to crack down on corrupt dealings. Merchant's daughter Yun Qianyu (Nancy Wu) is an eloquent speaker. Under Gongsun Ce's guaidance, she eventually becomes a consel. Ji Niannian (Elaine Yu), a maid from Gaochang, is an autopsy expert. These two ladies help Kaifeng Seven unravel bewildering cases. However, danger is lurking everywhere in Kaifeng Prefecture. Guard Tutor Pang (Li Shing Cheung) is a bully, who repeatedly frames Bao Zheng. Bao Zheng and Niannian get along very well. Love gradually grows between them. But when he finds out her true identity, he senses some hidden disaster is looming. Qianyu's father Yun Zhongliu has some strange ambition as he points out the emperor's heritage is questionable. Bao Zheng has to handle the most difficult case yet as he faces the dilemma of revealing the truth or abandoning his conscience for the sake of his country.