Diễn viên chính

• Kim Soo-hyun vai Baek Seung-chan[9][10]
  • Park Sang-hun vai Seung-chan lúc nhỏ
• Cha Tae-hyun vai Ra Joon-mo[11][12][13]
  • Gil Jeong-woo vai Joon-mo lúc nhỏ
  • Chae Sang-woo vai Joon-mo thiếu niên
• Gong Hyo-jin vai Tak Ye-jin[14][15][16][17]
  • Lee Ji-won vai Ye-jin lúc nhỏ
  • Ha Seung-ri vai Ye-jin thiếu niên
• IU as Cindy[18][19][20]
  • Park Seon vai Cindy lúc nhỏ

Diễn viên phụ

• Kim Jong-soo vai Baek Bo-sun, bố Seung-chan
• Kim Hye-ok vai Lee Hoo-nam, mẹ Seung-chan
• Park Hee-von vai Baek Jae-hee, chị Seung-chan
• Park Jong-hwan vai Baek Young-chan, anh Seung-chan
• Choi Sun-young vai Baek Yoo-bin, em gái Seung-chan
• Kang Shin-chul vai Myung Ji-hoon, chồng Jae-hee

• Seo Ki-chul as Jang In-pyo, director of the variety department
• Park Hyuk-kwon as Kim Tae-ho,[21] chief producer of the variety department
• Kim Jong-kook as Kim Hong-soon, PD of Open Concert[22]
• Ye Ji-won as Go Yang-mi, office manager of the variety department
• Lee Chae-eun as Son Ji-yeon, writer of the variety show 2 Days & 1 Night[23]
• Ko Bo-gyeol as Wang Min-jung, youngest writer on 2 Days & 1 Night
• Bae Yoo-ram as Ryu Il-yong, assistant director on 2 Days & 1 Night
• Shin Joo-hwan as Hyung-geun, assistant director on 2 Days & 1 Night
• Lee Joo-seung as Kim Joon-bae, floor director on 2 Days & 1 Night. Turns out to be a legendary ghost on KBS.
• Susanna Noh as publicist on 2 Days & 1 Night
• Kim Sun-ah as Kim Da-jung, youngest writer on Music Bank
• Jang Seong-beom as assistant director on Music Bank

• Na Young-hee as Byun Mi-sook, the CEO
• Choi Kwon as Cindy's road manager
• Jo Han-chul as Secretary Kim
• Janey as Jini
• Na Hae-ryung (of Bestie) as Yuna
• Jo Seung-hee as Yu-ju, member of Pinky4
• Kim Soo-yeon as Christine, member of Pinky4
• Jung Mimi as Ha-neul, member of Pinky4
• Park Seo-yeon, young trainee
• Lee Ji-ho, young trainee
• Kim Ye-won, young trainee
• Lee Seo-yeong, young trainee
• Kim Jong-Kook, Kim Hong Soon

• Gi Ju-bong as Park Choon-bong, the president of KBS
• Im Ye-jin as Park Bong-soon, Joon-mo's mother
• Kim Hee-chan as Tak Ye-joon, Ye-jin's younger brother
• Jung Han-hee as Kim Tae-ho's daughter
• Yoon Yoo-sun as Kim Tae-ho's wife
• Kim Sa-kwon
• Lee Du-seok
• Jo Chang-geun
• Jin Yong-wook
• Jeon Heon-tae
• Hwang Min-ho
• Ahn Se-ha as manager
• Lee Jeong-ho as Reporter Kang

Guest/cameo appearances