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"Moon Lovers: Scarlet Heart Ryeo" is a South Korean historical drama that aired in 2016. It stars Lee Jun-ki, IU, Kang Ha-neul, Hong Jong-hyun, Nam Joo-hyuk, Byun Baek-hyun, and Seohyun. The drama is based on a Chinese novel titled "Bu Bu Jing Xin" by Tong Hua. The story follows a modern-day woman who travels back in time to the Goryeo Dynasty and becomes involved in a royal power struggle.