Dongdong (Anita Mui) and Xinjing (Michelle Yeoh) were adopted by a martial arts master when they were young. He taught them martial arts in the hope that they would grow up to be chivalrous and righteous. The two orphans were like sisters. Unexpectedly, Xinjing was captured at the age of 12 and has not been heard from since. Dongdong married police officer Liu Qiwen (Damian Lau) when she grew up, and became a good wife and mother after giving birth to a daughter. For many years, she has concealed her identity from her family, but the couple became estranged because of this. Xinjing was captured by the Qing Dynasty eunuch Chen Gonggong, who used poison to wash away her memory and used her good skills to do bad things. Chen Qi (Maggie Cheung) is also the eunuch's subordinate. She is unruly by nature. She was not deeply poisoned and her memory was restored soon. She is as righteous as Dongdong, but she values money more than life. The three met in a fight to steal a baby, but their sense of justice made their originally opposing roles evolve into a common direction to deal with female warriors who endanger the lives of the public.