A period gangster story in which two brothers emigrate to Shanghai, but end up mixed up in some gang shenanigans - resulting in one of them getting killed and the other avenging his death by going into the criminal underground.

The story tracks two brothers striving to establish themselves in Shanghai, where they swiftly integrate into a formidable gang. While on duty at a brothel, the younger sibling, Fay (Chang Jian-Li), finds himself in a confrontation with a xenophobic foreigner - culminating in him being shot down. His older brother, Fong (Lau Sek-Ming), sacrifices himself by claiming responsibility for the murder and is incarcerated, leaving Fay to muster the funds for his release, navigating Shanghai's pervasive corruption. Fay resumes his gang activities and is tasked with going undercover to ascertain whether a rival faction led by Shu (Wang Hsieh) is collaborating with the invading Japanese forces. In his undercover role, Fay clashes with Shu's unscrupulous lieutenant and martial arts expert, Ti Chi (Zhang Feng-Yi), escalating into brutal violence.