Plot
Choi Young-Jin (Kim Hee-ae) is a female detective squad chief. She also raises her daughter Ha-Eun. At work, she deals with brutal crimes with her senior detective Park Jong-Ho (Kim Min-jong) and squad members Min Do-Young (Lee Da-hee), Han Jin-Woo (Son Ho-jun), Jo Jae-Deok (Heo Jung-do) and Lee Se-Won (Lee Gi-kwang).