Given the fact that a bunch of people cared to rate this title, I am surprised none of them has written a review so far, so I am going to do it especially because I liked the series. It presents a team of detectives who try to solve their cases, out of which one in particular seems to connect their lives through unknown threads, over a period of five years.
I would say that the strong point of the film is the story itself, a story whose end we can't really anticipate and whose resolution we will only find in the final episode. The acting is also remarkable, and I can't help noticing how versatile an actor Song Il-Guk is. Song Il-Guk and Song Ji-Hyo are a couple we ship ( apparently not for the first time!), and a good thing is, again, you won't know what happens to the fans' desire until the final scene. Not being an expert in the making -of the movies, I really couldn't tell how good the editing is, but somehow I expected something better from the scene where the characters fall from a high building.
The plot has a few twists which make it interesting to watch, so all in all I would recommend the series if you want a break from period dramas.