My friends recommended this drama, and I jumped to it right after Beyond Evil, which might have affected my judgment. I would say it started off strongly then it dropped when we had so many unexplored plot lines and the OZ organization was like a balloon that promised to pop only to wither away quietly.
I want more crime/thriller Korean dramas Mouse was good but they had many weaknesses that would be better fixed for the next drama.
So, what I liked were the acting Lee Seung Gi and the supporting cast all did a great job, Ko Mo Chi would do nicely in comedy and I love his short-fused reactions. The child actor would be a great actor in the future, overall it was a good watch, I recommend it.