"When a judicial apprentice goes behind bars while on an undercover job, he plays the hand he’s dealt to survive prison and get his payback."
Kang Ha-neul
as Kim Yo-han
Lee You-young
as Oh Soo-yeon
Heo Sung-tae
as Yoon Byung-wook
Kim Sang-ho
as Mok Jin-hyung
Kang Young-suk
as Jang Seon-oh
Park Seong-geun
as Hong Sang-wook
Kang Shin-hyo
as Hong Jae-seon
Jeong Man-sik
as Yang Hwa
Kim Si-eun
as Park Ro-sa
Sung Ji-ru
as Heo Sang-soo
Cha Yeob
as Kim Gil-sang
Yoon Byung-hee
as Kim Woo-sang
Lee Dong-won
as [Seongju Prison inmate #1321]
Moon Sung-keun
as Do Won Bong [Seongju Prison inmate]
Heo Dong-won
as Yang Jun ['Skin Nation' chairman]
Choi Dae-hoon
as No Seung Hwan / Nam Dae Moon [Seongju Prison inmate]
Han Jae-yeong
as Jo Hae Do [Bukyeongpa gang]
Kim Ji-na
as Jin Soo Min [Director / 'Skin Nation' accountant]
Oh Tae-kyung
as Woo Sang Ki [Goldman Casino's accountant / Min Ho's father]
Choi Moo-seong
as Song Doo Cheol [Bukyeongpa gang]
Han Kyu-won
as Eom Ik Soo [Bukyeongpa gang]
Jo Hee-bong
as Ryu Tae Hoon [Seongju Prison inmate]
Lee Ha-yul
as Kim Woo Jae [Prosecutor]
Kim Min-seung
as Woo Min Ho [Sang Ki's son]
Yoo Ha-bok
as Kim Jung Gyu [Prosecutor]
Kim Byung-cheol
as [Sinseondong elder]
Seo Myung-chan
Lee Yang-hee
Jeong Hwee Wook
as Kwon Dae Il [Police]
Moon Jong-won
as Kim Sung Bum [Seongju Prison staff]
Park Joong-geun
as Park [Seongju Prison guard]
Kim Kyu-baek
as [Seongju Prison inmate #1369]
Hwang Dae-woong
as [Seongju Prison inmate #8934]
Kim Wang Do
as [Seongju Prison inmate #7721]
Min Yeon-hong
Director
Moon Man Se
Writer