"I Saw the Devil" tells the story of Kyung-chul, a psychopath who loves crime and the murder is an art given the diabolical and twisted methods used to end their numerous victims, all young girls. But the choice of one of them overturns his work, one of the young daughter of a retired police detective, and in the same boyfriend, also an actor, take revenge and personal goal. The clash of the titans is served.
The film does not detract from the style of great games of the genre of serial murderers, such as "Seven" or "Zodiac", but complements it with large doses of blood and bloody creativity in the modus operandi of the criminal, that might have been pupil of the legendary puzzle, villain of the saga "Saw" and seasoned with hints of black humor. This, he creates a quality film that makes the viewer travel through the roller coaster of his script and splash of blood and guts on the road, a good product but not for all tastes ... not all stomachs.
Filmed with a masterfully staged and memorable performances is a round product in a movie style and to consider and add to the short list of hits that blend a serious plot with an aesthetic and bloody gore. If anything can play against perhaps its very long duration only inviting stretch the viewer's attention more than a stretch, but the director knows recovered with surprising plot twists or visual.