Yoo-mi was charmed by Jin-wook's sly and playful personality, and they unexpectedly spend the night together.
However, Yoo-mi disappears in the morning, leaving Jin-wook feeling perplexed and irrationally angry.
How can a mermaid from the Joseon era survive in modern-day Seoul?
Shim Chung is a mermaid who finds herself transplanted to modern times.
But Joon Jae’s friend, Cha Shi Ah, who works as a researcher at KAIST, may be Chung’s only hope for surviving in her strange new world.