A new type of ice drug appeared in A City. Mo Gao, the deputy captain of the anti-drug team, targeted the drug dealer "Lame" but due to a mistake made by the young police officer Wu Haowei, the lead was lost. Mo Gao later found out that the drug dealer who came to A City was Tao San, an old rival of Captain Liu. Wu secretly followed Mo Gao and discovered that their informant was Man Lian. While searching for clues, they were discovered by Tao San's top henchman, Tattooed Arm, but luckily Man Lian claimed that Wu was his subordinate and they escaped unscathed.To make up for his mistake, the eager-to-succeed Wu requested an undercover operation. Wu and Man Lian kept buying drugs from Tattooed Arm, taking the opportunity to propose a large-scale transaction to lure Tao San to appear. During the transaction, Man Lian's identity was suspected, and Mo Gao insisted on pursuing, resulting in an explosion that injured Mo Gao and killed Man Lian.