- ICAC rookies Auyeung Chi (Carlos Chan) and Shum Wing-Kwan (Jeannie Chan) are led by senior investigators Cheung Ka Man (Joyce Tang) and Hon Yik Shan (Ben Wong) to probe into intractable cases such as "Teachers soliciting money from parents", "Conspiring to forge roadworthiness certificates", "Kickbacks in high-end restaurants", etc.
Gradually, they are able to handle tasks independently. Later, Shan decides to quit his job to start a new career for his own good. Suddenly, the ICAC receives complaints about former high-ranking government official Kan Tung Yiu (Kent Cheng) accepting rent-free use of luxury units. Assistant Director of Operations Wong King Sun leads Ka Man, Chi and Kwan to launch a thorough investigation, only to find the opposing counsel turns out to be Shan. In the meantime, Ka Man has to step down due to illness. Thus, Chi and Kwan take it upon themselves to combat corruption, pledging a victory in Hong Kong's graft-busting efforts!