The King: Eternal Monarch

Goo Seo Ryung

[Seo Ryung's mother]

[Rookie] (Ep. 16)

Noh Ok Nam [Head court lady who raises Lee Gon]

Secretary Mo [Lee Gon's general secretary]

Lee Gon [Young] (Ep. 1, 4, 9, 16) | Lee Ji Hun (Ep. 1)

Yoo Gyung Moo [Yi Rim's subordinate]

Mr. Kim [Seo Ryung's assistant]

Kim Gi Won

[Military official] (Ep. 6)

Park Jung Gu (Ep. 7-8)

[Arcade worker] (Ep. 5, 7)

Lee Sang Do (Ep. 2) | [Stable worker] (Ep. 7, 9, 11-12)

Song Jung Hye

Goo Seo Ryung [Young]

[Jo Young | Jo Eun Sub's father]

Jo Ha In [Psychiatrist]

[Seo Ryung's advisor]

Lee Jung Hoon [Horse doctor] (Ep. 5, 7, 9)

Seung Heon [Yi Jong In's eldest son] (Ep. 1, 11, 15)

Jung Do In [Jung Tae Eul's father / Taekwondo instructor]

[Gambling boss] (Ep. 3-4, 9)

Jo Eun Sub | Jo Young

Yi Jong In [Member of the royal family]

[Eun Sub's mother] (Ep. 10)

Myung Na Ri [Building owner] | Myung Seung Ah [Employee on duty at the Royal Press Office]

Jo Young [Young] (Ep. 1)

Yi Rim | Lee Sung Jae

Shim Hyung Sa [Homicide detective]

Kim Bok Man (Ep. 1-2)

[Prime Minister's son] (Ep. 16)

King Yi Ho [Lee Gon's father] (Ep. 1, 4, 14)

Jang Michael [Homicide detective] | Jang Mi Reuk [Royal guard trainee] (Ep.13)

Kang Shin Jae | Kang Hyun Min [Young] (Ep. 7-16)

Park Moon Shik [Team leader]

Choi Gi Taek (Ep. 4, 6)

Choe Min Heon [Chairman] (Ep. 9-10)

Min Hwa Yun [Shin Jae's mother] / Park Sook Jin / Min Son Young [Palace staff]

[Gang boss] (Ep. 3, 8)

Kyung Ran [Tae Eul's fellow police officer]

Jung Tae Eul | Luna

Lee Gon

[Hyo Jin's mother] (Ep. 16)