The case files of Seoul city's metro police investigative squad. Captain Go Ji-seok partners with police investigator Yoo in-order to capture a serial-killer in a fight for justice.
EPISODE 1
Episode 1
Seoul city's metro police investigative squad celebrates its 30th anniversary and is tasked with convicting a petty thief. Yoo-ryung reads an advertisement for new recruits and applies to the squad.
EPISODE 2
Episode 2
Yoo-ryung hears suspicious noises whilst on patrol and enters an off-limits area. Captain Go Ji-seok finds Yoo-ryung unconscious and warns her never to enter again.
EPISODE 3
Episode 3
Investigator Yoo faces an internal review for shooting at a felon. The review board takes the issue very seriously in order to avoid media controversy.
EPISODE 4
Episode 4
The Seoul city metro investigative squad investigates a case of contract killing. The squad seeks evidence and witnesses.
EPISODE 5
Episode 5
Kim Won-tae is arrested for charges of assault and battery. After a search, it is revealed an ex-girlfriend of his was murdered. However, his girlfriend declines to have him detained.
EPISODE 6
Episode 6
Captain Go and Yoo-ryung investigate a rumour which states that on the last Friday of every month an all-night clubber disappears on the first train. Captain Go tails a petty thief.
Moon Geun-young
Kim Seon-ho
Jung Yoo-jin
Ki Do-hoon
Jo Jae-yoon
Ahn Seung-gyun
Song Ok-sook
Ahn Sang-Woo
Nam Gi-ae
Kim Jung-young
Shin Yoon Sup
