I'm gonna start with the story, the story was very attractive and because of this I was disappointed. I mean who wouldn't like a story with three badass FLs.
1) The story/ the ending, in particular, was predictable
2) The team was lacking, what I mean by that is there too many unnecessary obstacles, and almost every now and then the team tries to obtain something they can't lay their hands on it. This was quite frustrating for me to watch.
3)The romance was a whole obstacle of its own, even though I considered Ye Eun (the expert at computer) and the celebrity to be a cute couple I thought the romance between the CEO and the main character was overwhelming considering the fact that she was an agent, and that to someone he knew from the past.
4) As much as I liked the actors, I felt like some of their actings was exaggerated.
5) The drama as a whole was unnecessarily dragged out.

I liked the action scenes and the team leader(Gwan Soo), those were probably the only things that kept me from being distracted while watching this drama. As someone who had been waiting for this drama for a while, I was really disappointed. The writer had us in the beginning but the writer just went astray. I expected something refreshing/new but it turned out this way.