en Cuevana 3. A new type of drug emerges in Harbor City, leading investigators to a two-year-old armed drug smuggling case—with all clues pointing to the Hongtu Group. Lu Yunlong, a recently transferred undercover agent, infiltrates the organization and gains the trust of its chairman, Li Hong, after saving his life. However, he soon discovers that the group's second-in-command, Chen Biao, is the very man who murdered his teammate years ago. Teaming up with fellow undercover agent Xu Li, Lu engages in a deadly battle against the drug cartel. Through life-and-death confrontations, they ultimately succeed in dismantling the entire syndicate.