Dae-hoon is a special agent whose pregnant wife becomes the latest victim of a disturbed and brutal serial killer. Vowing revenge, Dae-hoon blurs the lines between hunter and hunted and good and evil, eventually becoming a monster himself in his twisted pursuit of revenge. I Saw the Devil is shockingly violent and stunningly accomplished, transcending the police procedural and pushing the boundaries of extreme Asian cinema in surprising and thrilling new ways.