Song Seung-hwan

as Audition Judge

as Lee Tae-hak (32 episodes)

as Self (archive footage) (1 episode)

Director

Director

as Yoo Kyung-Ho (54 episodes)

as Jang Chul-woong (54 episodes)

as Hee Myeong (40 episodes)

as Radio DJ

as President Park (16 episodes)

as 박재하 (2 episodes)

as Yeom Byeong-ryeol (87 episodes)

as Ha-young

as Host (1 episode)