After getting approval from his superiors, young anti-narcotics cop Chen Zheng (played by He Shengming) changes his identity and goes undercover in a drug manufacturing factory. He teams up with Jiang Hai (played by Wang Yiquan) outside the factory to plan to uproot a large gang of drug makers and smugglers led by He Yuanhua (played by Yu Entai). During this period, he was repeatedly tested and threatened by cunning drug lords.