Park Young Han is a young detective from Hwangcheon. He becomes furious at the reality of human dignity being violated and he struggles to deal with it. He teams up with his colleague detectives at the Jongnam Police Station in Seoul.
E1
Detective Yeonghan's capture of the gang's second-in-command, Salmosa, sparks chaos at the station.
E2
Yeonghan recruits to Unit 1 the fiery Sangsun, the mighty Gyeonghwan, and the elite Hojeong.
E3
Yeonghan warns of robbers heading to Seoul, but Senior Superintendent Choi dismisses his concerns.
E4
Yeonghan suspects the orphanage director's involvement while delving into a missing infant case.
E5
Devastated by the sudden death, Yeonghan sets a trap to apprehend the prime suspect, Viper.
E6
An officer falls prey to a sudden attack. Baek Doseok, a former military policeman, joins the team.
E7
A tragic suicide case emerges. Yeonghan leads the investigation and uncovers the hidden truth.
E8
Two violent crimes occur overnight, and Unit 1 handles both cases due to the lack of personnel.
E9
A missing worker's body is found, prompting Yeonghan to suspect a group of influential figures.
E10
Yeonghan discovers Doseok's secrets, prompting Doseok to hatch a sinister plan.