Lee Joon Ki as Wang So, later King Gwangjong (4th Prince)
Kang Ha Neul as Wang Wook, later King Daejong (8th Prince)
Hong Jong Hyun as Wang Yo, later King Jungjong (3rd Prince)
Kim San Ho as Wang Moo, later King Hyejong (1st Prince)
Yoon Sun Woo as Wang Won, later Crown Prince Hyoeun (9th Prince)
Byun Baek Hyun as Wang Eun, later Prince Gwangjoowon (10th Prince)
Nam Joo Hyuk as Wang Wook / Baek Ah, later King Ahnjong (13th Prince)
Ji Soo as Wang Jung, later Vice King Moonwon (14th Prince)