A young Englishman abroad, Michael, visits the local low-life spot of Tiger Bay to test his assertion that the spirit of human romance survives even in the most unpromising of circumstances. He intervenes when a local criminal protection racketeer targets a Chinese nightclub, and falls in love with the owner's young English foster-sister. But Olaf's gang have only just started their campaign against Lui Chang, the cultured, elegant woman who owns the premises... and she is determined not to be intimidated or driven out of business under any circumstances...