Bloody and bold, "I Saw the Devil" is both the latest piece of horror-shock to emerge from South Korea and also something of a rebuking examination of the same. Directed by rising genre-star Kim Jee-woon, the film follows a government agent — meaning he knows how to get things done — as he goes off the rails when his fiancée is brutally murdered. Hunting down her killer, he becomes a relentless machine, burning with a quietly intense rage for revenge.
The agent (Lee Byung-hyun) quickly locks into a brutal game of cat and mouse with the stone psycho (Choi Min-sik) who committed the crime, and they look to one-up each other in all manner of excruciating physical and psychological torture. In some ways Kim's greatest achievement in the film is the way he keeps a viewer teetering as to which character is the "I" and which is "the Devil" of the film's title.
Even at its most chaotic, the film never loses sight of the human toll of the increasingly over-the-top events it portrays. There is all the violent mayhem, for certain, but the thing that sets "I Saw the Devil" apart is its undercurrent of real emotion and how unrelentingly sad it can be.