Gangnam B-Side

In the neon glow of Gangnam, a girl flees into the street to escape her pursuers; detective Kang Dong-woo, broker Yoon Gil-ho and prosecutor Min Seo-jin are each pulled into yet another missing persons' case in Gangnam.

Dongwoo returns to Gangnam to find it changed as Gilho faces danger while chasing down the suspect.

Dongwoo has an unexpected encounter when he investigates in Gangnam using the crucial piece of evidence left by Yoon Gilho; when the investigation takes a dark turn, Seojin asks for Dongwoo's help; Gilho receives unsettling news while chasing Jaehee.

After being rescued by Seojin, Gilho tells Dongwoo and Seojin that the Colosseum holds the key to the Gangnam missing persons' case; Jaehee rushes to the Colosseum to save her abducted friend and Dongwoo, Gilho and Seojin are right behind her.

Jaehee heads over to meet Choi Hakgu to save Yeseo; Dongwoo and Gilho try to rescue Jaehee.

Seojin climbs the ranks with the help of Hakgu; Dongwoo becomes a chauffer and hunts for Yeseo.