Yes, Kim Soo Hyun did a great job but you can't overlook the damning lack of coherent story. While I could distinguish the different egos, by the end I was losing track of them. The filming overall was good and there are many beautiful scenes, but the action scenes (especially sound effects) were almost laughable. I wouldn't mind that so much if I could actually understand what the hell was happening. I thought by the end I would have understood a little more but it only became more bizarre. I normally enjoy films which are something dark and different but I have to be able to follow a plot, which this lacked. The acting is definitely not something to laugh at, which saddens me as they put on a great performance for a poor script. The soundtrack is your standard action movie with no notable tunes.

I would say if you're a Kim Soo Hyun fan then sure, have a go at it, but it isn't anything like a K-drama (nudity, drug use and violence), and you won't finish it with any more understanding than when you started.