"The Legend of the Blue Sea" is a series about the tragic love story between a mythical creature and a human, which cyclically repeats in the modern world. Several centuries ago, a strong storm washes ashore a beautiful mermaid. Young advisor Dam Ren falls in love with Seo Woo at first sight and frees her from the governor's captivity. Hundreds of years later, playboy and con artist Chun Jae encounters a vaguely familiar strange girl, Shim Cheong...