Prisoner 701: Sasori (2008)
When a band of assassins invade the home of their target Hei Tai they find only his lovely, innocent, bride-to-be, Nami and force upon her a cruel dilemma: either she kills her fiancee’s sister or they kill her fiancee. Trapped, and unable to confide in the person she loves most, Nami kills her fiancee’s sister and is sent to prison where she survives only by becoming as ruthless as those around her. Trained to fight by a fellow inmate, Nami develops the skills and strength to escape and sets out on a quest for revenge. After killing two of the assassins she’s reunited with Hei Tai who’s still unaware she killed his sister. As their love is rekindled Nami decides to abandon her crusade of vengeance when the remaining assassin finds them and tells Hei Tai what Nami did. Nami realizes she can never rest until she finds and defeats the assassins’ employer, but now her beloved’s torn between helping her and his own personal desire for revenge.