Basically the South Korean version of Taken(this review has no spoilers)
I absolutely love this movie. It's more slow paced than Taken, as Asian films tend to be, yet it achieves much the same level of excitement and anticipation as the hero zeros in on his enemies. If you thought Liam Neeson is a man of few words in Taken, then Cha Tae Shik (played by Won Bin) really takes this to the next level. He utters about 5 sentences in the entire movie! But there is plenty of dialogue between other characters to compensate.
The fight scenes are great - believable martial arts and shootouts, and the villains are so morally despicable that you feel no remorse for the gruesome ways they die. Won Bin is perfectly suited to his role as the cool, emotionally damaged hero. For more comparisons, see my review of Taken.