Full cast of Secret Door

Lee Je-hoon

Crown Prince Sado

24 episodes

Kim You-jung

Seo Ji-dam

24 episodes

Yoon So-hee

Seo Ji-dam / Park Bingae

24 episodes

Han Suk-kyu

King Yeongjo

24 episodes

Park Eun-bin

Lady Hyegyeong

24 episodes

Kim Min-jong

Na Chul-joo

24 episodes

Lee Won-jong

Park Mun-su

24 episodes

Kwon Hae-hyo

Seo Kyoon

24 episodes

Jeon Kuk-hwan

Lee Jong-sung

24 episodes

Jang Hyun-sung

Hong Gye-hui

24 episodes

Uhm Hyo-seop

Min Baek-sang

24 episodes

Kim Ha-kyoon

Kim Sang-ro

24 episodes

Choi Won-young

Chae Je-gong

24 episodes

Seo Jun-young

Shin Heung-bok

24 episodes

Ha Seung-lee

Queen Jeongsun

24 episodes

Park Hyo-ju

Woon-shim

24 episodes

Kim Tae-hun

Kang Pil-jae

24 episodes

Jeong Gyu-su

Yang Soon-Man

24 episodes

Kwak Hee-sung

Kim Moo

24 episodes

Jo Woo-jin

Lee Dal-seong

24 episodes

Kim Woo-seok

Lee Seon [Young] / Lee San [Young]

24 episodes

Lee Won-jae

Kang Seo-won

24 episodes

Kim Hyun

Jang Hwa Won

24 episodes

Kim Chang-wan

Kim Taek

24 episodes

Son Byung-ho

Kim Sung Ik

24 episodes

Yoon Seo-hyun

Cheon Seung Se

24 episodes

Park So-eun

Shin Go-eun

24 episodes