What a mixed bag this drama was. While the quality of acting and special effects was outstanding, the ultimately weak, far-fetched plot was what really dragged this show down. A twist on the trope of the whole drug dealer/undercover cop scenario, this story's angle shone the spotlight more on the lengths that the 'good' guys will resort to, to get what they want or achieve what they consider 'right', regardless of the means used or the collateral damage.
I found the ending a huge disappointment; by the final episode you're really glad to be finally finished with Ji Chang Wook's character, who was an ambitious, selfish, jealous little toad from the outset.
Supporting male characters were excellent, particularly the knife-wielding lunatic Chief Seo, but as usual the female characters were weak pitiful creations, designed only to support the male lead. Shameful writing.
Really glad to be finished with this one and move on to something hopefully better.