Um Hyo-sup

Yoo Sang-won, Minister of Land, Infrastructure and Transport

Philip's father

Oh Wook-hwan

Inspector Park Jae-won

Park Gyeong-bae

Yu-jin's father

Ye Hyun-ho

Kim Hae-jin Im Ji-kyu as young adult Hae-jin (cameo, Ep. 11-12)

Kim Chun-gil, famous painter, 58 years old, currently missing from a lawsuit against netizens. Everyone believed that Kim Min-jae killed and buried him in Yongho Mountain.

Yi Bang-woo, "Grand Prince Jinan" (진안대군; 鎭安大君).

Lee Chang-geun

Park Pil-hong

Kwon Hae-ryong

Won Doo-jung

Goo Man-su, Goo Ra-ra's father and President of Rara Cosmetics

Baek Ja-yong

Kang I-moon

Eun Byung-ho

Head Referee

Eun Moo-young

Kim Kwi-chang

Shim Woo-cheol

Lee Sang-yeop

Lee Seung-hyu, Eun San's teacher

Heo Jun, a legendary physician from the Joseon period who was active during the reigns of King Seonjo and King Gwanghae.

Kim Ho-joon, Louis' butler

Senator Choi

Jin Myung-hoon – Seo-woo's father and Gookil Hospital's director.

Hong Yeong, Hong Joo-won's father

Go Jae-woong, Yi-seok's father

Kang Sung-wook

Jung Hwe-ryung

Da-jung's father

Jang Guk's father

Cheon Min-goo, Song-yi's father

Choi Won-jae

Oh Chul-min (32)

Park Mu-sol

Han Jung-woo

Uhm Dae-woong "Uhm Force", math teacher

Park Sun-woo

Minister Min Ahm

Yi Gae, former teacher of Kim Seung-yoo, Shin Myeon and Jeong Jong

Baek Sa-geong

(cameo, ep 12-13)