This drama is highly overrated..It had really good potential at the beginning but it slowly drags down.The romance in the drama is really forced,as the series goes on we can understand why female lead has some feelings for the guy but on the other hand the main lead's dialogues doesn't seem so realistic.Also the story was good but the puzzle which is the scenario gets heaviliy based on is solved early and the scenario gets repeated afterwards.Casting was good except Seo In Guk.I actually thought that Seo In Guk wasn't the right choice.He was lacking the necessary expressions as an actor. Overall,this drama had a great potential but it ended like a typical drama with a lot of cliches.I don't recommend it.