Main cast •
Eric Mun as Chil-woo (), sergeant at the
Uigeumbu in Seoul • Choi Su-han as young Chil-woo •
Koo Hye-sun as Yun So-yun (), government slave at
Uigeumbu • Lee Han-na as young So-yun •
Yoo Ah-in as Heuk-san (), adopted as Kim Hyuk () by Kim Ja-seon • Ku Bon-sung as young Heuk-san •
Jeon No-min as Min Seung-guk (), historiographer of
Ch'unch'ugwan •
Lee Eon as Jaja (), former bodyguard of Crown Prince Sohyeon •
Im Ha-ryong as Choi Nam-deuk (), Chil-woo's adoptive father •
Song Ha-yoon as Yeon-du () • Jang Jun-yeong as Cheol-seok ()
Extended cast •
Kim Young-ok as Chil-woo's adoptive grandmother •
Choi Ran as Chil-woo's adoptive mother •
Im Hyuk as
Chief State Councilor Kim Ja-seon () •
Choi Jung-woo as
King Injo • Song Yong-tae as
Uigeumbu Commissioner • Jeong Won-jung as
Uigeumbu Captain • Son Kwang-eob as Lieutenant at
Uigeumbu • Jeong Jin as Sergeant Sa () •
Shin Seung-hwan as Sergeant Oh () • Park Jun-seo as Sergeant Jeong () • Nam Myung-ryul as Jin Mu-yang (), birth father of Heuk-san • Park Yong-gi as Heo Won-do () •
Park Bo-young as Woo-yeong (), Chil-woo's younger sister • Kim Byeong-chan, as Butler Song () • Oh Ji-young as Han Do-yeong's mother • Cha Jae-dol as Han Do-yeong () • Kang Jae as Jo An-jung (), Son of Jin Sang-gun • Lee Ho-seong as Jinsang-gun () •
Han Ye-in as Seo Geum-ok (), daughter of the murdered night watchman •
Woo Hyun as Kim Mal-jung (), interpreter • Park Hyo-bin as Sam-wol () • Ko Jeong-min as Ok-byong (), famous woman poet Seok Hyeong • Kim Hong-pyo as Kim Jo-hyeon () • Lee Ji-eun as Song Ju-hee () • Jeon Yeong-bin as Mak-su (), leader of Heuk-san's militia •
Lee Seung-hyo as Boon-nyeo () • Min Ah-ryeong as Min Eun-hee (), Min Seung-guk's sister • Kim Ju-yong as Yong Gol Dae (), General of
Qing • Son Il-kwon as Lee Chi-seo () •
Kim Kyu-chul as Choe Won-sik () • Nam Seong-jin as Jo Seong-du () • Yang So-min as Crown Princess Minhoe () of the Gang clan, Wife of Crown Prince Sohyeon () •
Lee Seung-hyung as spy
Yusaeng () •
Moon Won-joo as Villager • Cha Soon-bae as
Park Geom-yeol ()
Cameos •
Nam Il-wu as Kim Hong-jo (), Woo-yeong's adoptive father (episode 1~3 & 13) •
Oh Man-seok as Kang San-ha (), Chil-woo's birth father (episode 1) •
Kim Ji-seok as Petitioner (episode 1) •
Kang In-duk as boss Woong-gi (episode 7) •
Im Ho as
Crown Prince Sohyeon (episode 13) ==Ratings==