Jeong Dong-hwan

as Nak-won

as Baek Jang -ho (1 episode)

as Bang Ki-ho (12 episodes)

as Cha Gi-baek (12 episodes)

as Choi Han-gyu

as Hwang Dong-woo (16 episodes)

as Oh Yeong-geun (12 episodes)

as Jung-su

as Park Jin-suk (16 episodes)

as Kim In-su (1 episode)

as President Han (16 episodes)

as Teacher Baek (32 episodes)

as Chae Byung-Hak (16 episodes)

as Noh Joon-suk (2 episodes)

as Kim Je-seok

as Lee Young-Joon (40 episodes)

as Lee Sun-Moon (16 episodes)

as Jang Tae-joon (20 episodes)

as Cha Jae-hwan (20 episodes)

as Byun Dae-sung (20 episodes)

as Han Pan-seok (102 episodes)

as Kim Geon-pyo (37 episodes)

as Chairman Kim Nam-yoon (20 episodes)

as Seo Dae-Seok (18 episodes)