Seo Sang-won

as Choi Chan-gu (12 episodes)

as Yoo Jin-tae (14 episodes)

as Sun-ah's father

as Park Jin-guk (1 episode)

as A-young's husband (1 episode)

as Cho

as Governor

as Yoon Tae-hwa (16 episodes)

as Doctor Kang [Soo Jin's father] (4 episodes)

as Won Tae-kyeong (16 episodes)

as Yoo Sun-Il (16 episodes)

as Director Ji

as Choi Jung Yun [Pilot] (1 episode)

as Jin-ju's father (16 episodes)

as Go Jin-beom (16 episodes)

as Congressman Park

as Professor

as Professor Bong (1 episode)

as Sung-hwan