It's rare that a movie combines extreme violence, visual panache, and gut-wrenching emotion, but Lady Vengeance is just such a movie. Geum-ja Lee (the lovely Yeong-ae Lee, Joint Security Area) is sent to prison at the age of 19 for kidnapping and murdering a 5-year-old boy. She becomes a model prisoner, apparently converting to Christianity and helping care for ill prisoners--but in fact, she's slowly making connections that will allow her to wreak revenge on the man responsible for her imprisonment. The first half of Lady Vengeance, in which Geum-ja Lee's plans are laid and her victim captured, spins to and fro in time with dizzying speed, moving fluidly among multiple narrative tracks. But once the man is in her clutches, the movie takes a turn that proves more harrowing and more emotionally complex than the previous films in writer/director Chan-wook Park's "vengeance trilogy," Sympathy for Mr. Vengeance or Oldboy--and if you've seen either of those films, you'll understand what a feat that is. These movies have much in common with the revenge tragedies written by contemporaries of Shakespeare; ornate plots full of extreme violence and perverse sex that delve into the darkest--yet often most vulnerable--sides of humanity. For all its sensational aspects, Lady Vengeance observes the toll of vengeance on the revenger; there's nothing cheap or easy about it. This movie, even more than Oldboy, demonstrates that Chan-wook Park is one of the most vital filmmakers of our time.