Shanghai, 1930. Mr. Tang, the godfather chief of the Tang family-run underground Green dynasty, controls the city's lucrative opium and prostitution trade. He has also acquired the services of Xiao Jinbao, the most beautiful prostitute-singer in Shanghai. Fourteen-year-old Tang Shuisheng has been recruited by his uncle to watch Xiao Jinbao. Ultimately, Shuisheng becomes the only person to whom she can talk openly and whose relationship with her is not motivated by power or greed. In secret, Xiao Jinbao has become the mistress of Song, the Greens' number two man, and together they conspire against Mr. Tang. Their plan fails, and Mr. Tang believes that his deputy will try to eliminate Xiao Jinbao for she was the only witness and accomplice. Using Xiao Jinbao as bait, however, Mr. Tang banishes her to a small, heavily guarded island where, a virtual prisoner, she gradually understands her role, realizing that the men in her life are ready to sacrifice her when she is of no further use.