The strongest point of this drama is by far the acting of the lead actors, especially Lee Joon Gi. When he broke down and whenever it got emotional, he aced those scenes and they were the best of all. I would argue that those scenes are what made the drama as successful. Because although the plot had some individual twists, the idea itself is nothing new. This is why it started a bit bland and mid but got better with each episode. But sometimes it was a bit slow. I also think that the whole memory loss plot line of the last episode could've been cut out. I can kind of understand why it was there, but it dragged the drama for another episode, which it did not need. But I loved the last scene and it was what I was looking forward to. The music was also great, especially during intense scenes, I could really feel the character's emotions.