Kim Nam Gil, Kim So-jin and Jin Seon-kyu are just amazing. They are born actors and actress. The episodes are well paced and it meticulously take us into the nitty gritty details of crime solving and the incompetency of those in the highest ranks (Who only knows how to talk and not do much and avoid responsibility and only step in when there are praises and rewards) in the police. I'm so glad they didn't put some idol actor or actress into the drama. The high ratings for the show proves that you still need great actors and actresses to carry the story and not just idol faces. Kim Nam Gil's range of facial expressions and at times solemn facial expressions truly brings out the realistic feelings of a criminal behavioural analyst.