Yu Oh-seong (b.September 11, 1968 in Gangwon), also spelled "Yu Oh-Sung", "Yoo Oh-Sung" is a South Korean actor.
as Jeong Doo-cheol(10 eps)
as Cheol-soo's father
as Jo Sang-tae(16 eps)
as Gil Seok / Chairman Oh
as Baek Mo-sa(12 eps)
as Tak In-hwan(16 eps)
as Seo-geom(16 eps)
as Yeon Gaesomun
as Seo Jong-Gil(36 eps)
as [Teacher]
as Self
as Choi Hyeon-joon(20 eps)
as Gil So-gae(41 eps)
as Choi Gook Jin(1 ep)
as Choi Ki-hoon
as Hwang Ki-chul(16 eps)
as Choi Won-shin(22 eps)
as Joon-seok
as Detective Oh
as Ki Chul(24 eps)
as Self(1 ep)
as Trainer Yoon
as Shingwi Ghan / Tae-gang(32 eps)
as Choi Gook Jin(1 ep)
as [Teacher](1 ep)
as Young-Suk
as Yun-jo
as Ahn Jung-geun
as Yeong-woo
as Kim Deuk-gu
as Joon-seok
as Mu Dae-po / Bulldozer
as Li Cheol-jin
as Sang-cheol
as Kang Dae Ho(1 ep)
as Tae-soo
as Baek-jun
as Jeom-pyo
as On-dal
as Hwang Nam-ki
as Nanyang University Theatre Class