Synopsis The series retells the love story between Princess Pyeonggang and On Dal, who are characters in a classic Goguryeo folktale. Princess Pyeonggang (Kim So-hyun) who was born as a princess but raised to be a person who killed a sinner also known as Yeom Ga Jin, an ambitious woman who dreams to re-establish the status of Goguryeo and be the first female Taewang of Goguryeo. However, she uses On Dal's (Ji Soo) feelings for her to achieve her goals. [About:] River Where the Moon Rises is an upcoming South Korean television series starring Kim So-hyun, Ji Soo, Lee Ji-hoon and Choi Yu-hwa. The series is based on the 2010 novel Princess Pyeonggang by a film director and screenwriter, Choi Sagyu. It is scheduled to air on KBS2 after Royal Secret Agent starting from February 15, 2021 every Monday and Tuesday time slot.