Having now seen all three films in
Park Chan-wook's
Vengeance Trilogy, I can really appreciate what a great director he is and what a talent he has for creating high-tension dramas revolving around the themes of violence, revenge, madness, and occasionally redemption. The films are all very well acted and directed with a visual poetry and precision that seems to be Park's signature style. The three films themselves aren't true sequels since the characters and events portrayed in each film are disparate with the exception of the through-theme of vengeance, kidnappings, imprisonment, and brutal violence.

In
Sympathy for Mr. Vengeance (2002) a young man and his girlfriend kidnap a little girl so that they can hold her for ransom in order to afford the young man's sister's kidney transplant, but things go horribly wrong triggering a downward spiral into violence that may never end.

In
Oldboy (2003) a man who has been locked away in isolation for fifteen years is by mysterious captors is released and goes on a violent revenge spree which leads him to a shocking revelation when he discovers the identity and motives of his twisted tormentor and kidnapper.

In
Lady Vengeance (2005) after being falsely imprisoned thirteen years for the murder of a little boy, a beautiful woman goes to extreme measures to realize her elaborate plan for retribution, to avenge the murders of six children, and to reunite her with her own long-lost daugther who she has not seen since going to prison.
The films are individually very impressive as examples of Asian melodrama infused with both visual poetry and gritty realism, but together as a trilogy they don't seem to stand side by side with the kind of symmetry a trilogy should possess. Each film boasts an variety of interesting action scenes, dramatic confrontations, and humorous encounters, but what makes each film unique are the fully developed characters who all share a bond of violence and madness. These characters are brought to life by amazing actors who really settle into the minds, bodies, and souls of their characters and inhabit the dark corners of their psyches.
For me, the first two films are stronger both in terms of direction and narrative storytelling, but all of them are worth a viewing and will exhilarate action junkies and enlighten foreign film fans together.