Moon Lovers: Scarlet Heart Ryeo (Korean Drama Ost) Starring: Lee Joon-gi as 4th Prince Wang So Lee Ji-eun as Go Ha-jin / Hae Soo Kang Ha-neul as 8th Prince Wang Wook Hong Jong-hyun as 3rd Prince Wang Yo Kim San-ho as Crown Prince Wang Mu Yoon Sun-woo as 9th Prince Wang Won Byun Baek-hyun as 10th Prince Wang Eun Nam Joo-hyuk as 13th Prince Wang Baek Ah Ji Soo as 14th Prince Wang Jung