Characters played by Park Hae-soo
Kim Je Hyuk
Characters played by Jung Kyung-ho
Lee Joon Ho
Characters played by Krystal Jung
Kim Ji Ho
Characters played by Kyoo-hyung Lee
Yoo Han Yang 'Loony'
Characters played by Jeong Woong-in
Lieutenant Paeng
Characters played by Moo-Seong Choi
Kim Min Chul
Characters played by Kang Ki-Doong
Prison Officer Song
Characters played by Kim Kyung-Nam
Lee Joon Dol
Characters played by Jung Hae-In
Captain Yoo Jeong Woo
Characters played by Park Ho-San
KAIST
Kang Chul Doo
Characters played by Hwa-Young Im
Kim Je Hee
Characters played by Ahn Sang-Woo
Prison Warden Kim Yong Chul
Characters played by Kim Sung-cheol
Beobja
Characters played by Park Hyoung-soo
Chief Na Hyung Soo
Characters played by Moon-Sung Jung
Yoo Jeong Min
Characters played by Min-sung Jung
Dr. Go
Characters played by Ahn Chang-hwan
Crony
Characters played by Soo-jung Ye
Je Hyuk's mother
Characters played by Jun-han Kim
Song Ji Won
Characters played by Joo Suk-tae
Yeom Sang Jae
Characters played by Sin Jae-ha
Kim Min Sung
Characters played by Won-Ho Shin
Corporal Joo
Characters played by Yoo Jae-myung
Je Hyuk's Lawyer
Characters played by Yeom Hye-ran
Han Yang's mother
Characters played by Seung-Yoon Kang
Jang Bal Jang
Characters played by Kyu-Sung Lee
Jung-Soo
Characters played by Jang Hyuk-jin
Han Yang's father
Characters played by Sung-won Choi
Jeombaki
Characters played by Seo Ji-Hoon
Ji Ho's friend
Characters played by Jae-Sung Jung
Professor Myung
Characters played by Dong-il Sung
Prison Officer Jo
Characters played by Kim Han-Jong
Daehyungsoji
Characters played by Kong Sang-Ah
Kim Ji-Ho's Mother
Characters played by Kim Ki Nam
Prison Officer Choi
Characters played by Lee Chae Yun
Kim Ji Ho (young)
Characters played by Sin Dong-ryeok
Reporter
Characters played by Jang Hae-Song
Han Yang's alumnus