Lee Joon-gi as 4th Prince Wang So Lee Ji-eun as Ko Ha-jin/Hae Soo Kang Ha-neul as 8th Prince Wang Wook Hong Jong-hyun as 3rd Prince Wang Yo Yoon Sun-woo as 9th Prince Wang Won Byun Baekhyun as 10th Prince Wang Eun Nam Joo-hyuk as 13th Prince Baek-ah Ji Soo as 14th Prince Wang Jung