A mermaid from the Joseon period ends up in present-day Seoul, where she crosses paths with a swindler who may have ties to someone from her past.

Set during the Joseon era, Hong Cheon Ki is a female painter with a genius like painting talent. She is picked as the first female painter of the Dohwaseo. Hong Cheon Ki also has a beautiful appearance and a bright personality. For her, painting is everything. One day, she meets Ha Ram.

In a story of two men switched at birth, noble-born Chun Doong lives as a slave and becomes a heroic outlaw, while beggar-born Gwi Dong lives as a nobleman and police chief; then each falls in love with the same girl, Dong Nyeo.