Sympathy for Lady Vengeance

Geum-ja is a woman imprisoned for the kidnap and murder of a five-year-old. Converted to Christianity in prison, her piety sees her released early but no one can imagine the vengeance she plans. Her obsession is with her high-school teacher Mr Baek, and flashbacks to Geum-ja's time in prison introduce her fellow prisoners whose skills may assist her in her task.