Queen of Fist

Queen of fist () is a 1972 Hong Kong action drama movie directed by Lung Chien and starring Hsien Chin-Chu as Kung Fu Mama, Zhang Qingqing as Ma Ai-Chen, Jimmy Wang Yu as Ma Yung-Chen, Kang Kai, Tzu Lan, Wong Fei-lung as the gang leader.
Plot.
An elderly mother travels to Shanghai to look for her missing children. She discovers that the boss Lin Hie killed his son and is holding his daughter captive.
So, she wants to kill the gang leader.