A great woman draws her strength from the people around her that Princess Pyeonggang/Ga Jin will draw from On Dal is undeniably clear. The first episode does a good job of setting up the different people involved in the drama, from Princess Pyeonggang to her mother, Queen Yeom, played by Kim So-Hyun. Her father, King Pyeongwon, played by Kim Bup Rae, whose rule was under attack by Go Won Pyo, played by Lee Hae Young, who in pursuit of power and monopoly of the salt trade at that time set up a trap for the Queen and manipulates the King into thinking his wife was cheating on him, which leads the King on a killing spree and authorizes the murder of his Queen. Jealousy, greed, and fear will always be the down of a weak man.
As a result of the trauma from the death of her mother and seeing her father on a killing spree, Princess Pyeonggang loses her memories; she taken-in by some mountaineers and ends up living her life as Ga Jin, as part of an elite group of assassins
targeting the royal family members, a role she excels in but doesn't like, and to end it, Ga Jin strikes a deal with her chief who promises to release her with one last mission, the assassination of King Pyeongwon (her birth father) and it's this mission that leads Ga Jin right back on the path of the palace and On Dal.
In so many ways, River Where the Moon Rises reminds me of My Country: The New Age, not so much in its story but the cinematography, fight scene choreography, impeccable directing, and editing. And as much as I'm enjoying Kim So-Hyun and Ji Soo in their respective roles, I would've liked to see more of Kang Ha Neul as General On-hyeop, On Dal's father. I loved his limited yet intense role (I read initially they'd offered the lead roles to Son Ye-jin and Kang Ha Neul, but they couldn't accept); nonetheless, the current leads are doing a superb job thus far. And Lee Hae Yong as Go Won Pyo is certainly leaving an impact on how he plays that role; great job.
I wouldn't at all be surprised if he's the one funding and ordering this elite group of assassins to get rid of the royal family and have ultimate control. Ga Jin doesn't strike me as someone who would fail at anything she does. I think she purposely left the message that Go Geon found. Not just as a warning but as a plea of help, for someone to stop her. I like how unpretentious and genuine On Dal is; I see why he and the simple life he lives appealed to Ga Jin. Watch Episode 2 here.