The movie is set in Shanghai in the early Republican era. Cheng Daqi, a young man working at a fruit stall, travels to Shanghai in search of a new life and he meets Hong Shouting, a police chief who is also a triad boss. Hong's wife, Ling Husheng, recognises Cheng's talent and successfully persuades her husband to let Cheng join them. Cheng gradually rises through the ranks in the criminal underworld of Shanghai and becomes an influential triad boss. He meets Bao, who falls in love with him, but Cheng's true love is actually his childhood friend Ye Zhiqiu, who has gone missing.

Many years later, a middle-aged Cheng has become one of the most notorious and powerful triad bosses in Shanghai, even surpassing his old boss Hong Shouting. However, he finds himself caught up in the struggle between the aggressive Empire of Japan, which is planning to invade China, and the local secret service led by the crafty Mao Zai, who saved his life many years ago. He also encounters his old flame Ye Zhiqiu again, but she is now married to another man.