The play is based on the legend of the mermaid in the earliest collection of Korean folk tales \”Yu Ye Tan\” in which Shegu County magistrate Jin Danling (played by Lee Min Ho) released mermaid caught by fishermen into the sea. It tells the story of the mermaid Sim Cheong (Jeon Ji Hyun) who came to the city on the brink of extinction hundreds of years later, adapting to life on land and the genius liar Xu Jun Jae (Lee Min Ho) reunited and fell in love