When You Want to Say Unspeakable Secret

Park Bo-gum

Lee Yeong / Crown Prince Hyo Myeong

Kim You-jung

Hong Ra-on / Hong Sam-nom

Jung Jin-young

Kim Yoon-seong

Chae Soo-bin

Jo Ha-yeon

Kwak Dong-yeon

Kim Byeong-yeon

Kim Seung-su

King Soonjo

Jeon Mi-seon

Consort Park Soo-ki

Heo Jung-eun

Princess Yeongeun

Jung Yoo-min

Wol-hee

Cheon Ho-jin

Premier Kim Heon

Jung Hye-sung

Princess Myeongeun

Jang Kwang

Eunuch Han Sang-ik