Martial Angel tells of Cat (Shu Qi), a professional thief turned straight after leaving her lover, Chi Lam (Julian Cheung), two years before. But her past returns to haunt her as Chi Lam is kidnapped for the ransom of security software belonging to the company Cat works for. In order to rescue him, she calls on her old friends from her orphanage days, six other feisty women, to save the day...