Plot: SIN-YAN becomes CHEUK HOI's undercover officer to carry out investigation on "Mr SUNG", the one manipulating all the criminal activities behind the scene. According to information from HEI-MEI, "Mr SUNG" is formed by the merchant TSUI GA-BO, the councilor POU YEUNG SUK-WAN, the Director of Public Prosecution KWOK CHING and the tycoon PONG YIN-TING