One day, a strange woman that goes by the name of Yeri appears in front of the just healed Seulgi. She reveals bits of Seulgi's past and the whereabouts of her family, or what's left of it. Appareantly there's this dictator, who eliminated anyone that was against him.

Yeri asks a favor from Seulgi, and it's to work for Bae's family, a rich and powerful linage, as a somewhat bodyguard of the eldest daughter Bae Joohyun, otherwise known as Irene, the apple of her father eye's. 

As she keeps up with her task, more and more secrets will be revealed, and what's good is wrong and who is a friend turns into an enemy. 

Bioshock insp!