Big Fly Hong of the Hung Sun Society

Big Brother Fei is one of the twelve chaperones of the Hong Xing society. The daughter of his subordinate, No-Tooth Guy, falls in love with the head of another organization, the Dongxing Society, known as Emperor. Emperor has a notorious reputation, and No-Tooth Guy does not want his daughter to be with him. Thus, he invites Big Brother Fei to negotiate with Emperor's superior, Big Brother Mi. Unexpectedly, Emperor and his superior declare in unison before Big Brother Fei that they are truly in love. Emperor even swears that he will never fool around with other women again. Unable to do anything, Big Brother Fei agrees for them to continue their relationship but warns Emperor not to betray her.

Emperor’s subordinates, like Shan Zi, cannot stand Big Brother Fei's authoritative demeanor and go to the sauna he operates to cause trouble. However, they get beaten up by Big Brother Fei's men and are chased out of the sauna naked. This incident leads to a grudge between Shan Zi and Big Brother Fei.

Big Brother Fei's former lover, A Ling, invites him to meet at the hospital. It turns out she is terminally ill. Before she passes away, she tells Big Brother Fei that she has given birth to his son, who is already years old. As Big Brother Fei is speechless upon hearing this sudden news, his son appears — it is none other than Shan Zi, who is fiercely opposing Big Brother Fei. Neither Big Brother Fei nor Shan Zi can accept this fact, but reality shows that they are indeed father and son.

The Dongxing Society collaborates with the Chaozhou Gang in drug trafficking. Emperor orders Shan Zi and others to transport the drugs but secretly sends someone else to seize the drugs and frame Big Brother Fei, claiming that this is a conspiracy between Big Brother Fei and Big Brother Mi. The Chaozhou Gang kills Big Brother Mi and sends people to chase after Big Brother Fei. Shan Zi accidentally hears this information and, driven by the nature of fatherhood, decides to inform Big Brother Fei. However, he is caught by Emperor, who uses this as leverage to force Big Brother Fei to comply.

Big Brother Fei decides to save his biological son and goes alone to the Dongxing lair. Emperor, prepared in advance, orders his men to surround Big Brother Fei. How will Big Brother Fei escape from this predicament? Will father and son finally recognize each other? And will Emperor receive his comeuppance?