Mainland undercover cop Gong Wei (played by Jet Li) cannot take care of his seriously ill wife due to work obligations, nor can he provide more care to his sensible and skilled son Gong Gu (played by Xie Miao). When his wife and son need him the most, Gong Wei is ordered by his superior to impersonate a criminal and escape with the captured Hong Kong gang member Xiao Hei (played by Kuo Shou Liang), embarking on a mission to infiltrate a gang led by Fu Guang (played by Yu Rong Guang) in Hong Kong. During a bomb deal, Gong Wei and Fu Guang's gang engage in black eating black, and in the midst of the chaos, he rescues Hong Kong inspector Fang Yihua (played by Anita Mui), winning Fu Guang's trust with his exceptional skills. Fang Yihua travels to Beijing to investigate Gong Wei's identity, learns the truth, and after Gong Wei's wife passes away, she leads Gong Gu to Hong Kong to find his father. However, Fang Yihua's superior exposes the identities of father and son, putting Gong Wei in a dangerous position, just as Fu Guang is planning a robbery at an auction that is fast approaching...