A by-the-book police officer is assigned to secretly investigate a team leader who believes that the rules shouldn't stop an investigation. As the officer investigates further, his own attitudes begin to mirror the team leader's.
After he leaves the police force, Dae-ho establishes himself as the sheriff of his town. He then investigates Jong-jin, a businessman, because of his alleged ties to drugs.
Trainee policeman, 'Sung-min' and job seeker, 'Jun-hyeok' were suspicious about a suicide incident of a girl who lived in the same dormitory, and they will be tracking her SNS account with the help of a private detective agency hacker, 'Nu-ri'. The investigation which started out of chivalry leads to uncontrollable consequences. These three people, Jun-hyeok, Sung-min, and Nu-ri become targets of SNS crime.
Jiwon, a motivated new police officer, is strangely bothered after meeting Osun, a social worker. On a hot summer day, a kidnapper sends a message saying, ‘If you want to save the kidnapped child, donate money to the welfare center.’ The incident becomes a national concern as the media report it. Somehow, Jiwon doubts the link between the case and Osun.