A story of the precarious yet tender first love of two 19-year-olds experience while selling an illegal item.

Six finalists for a global IT job are pushed into a tense team debate where only one can win, exposing their true selves under pressure. Among them is Jeon Yo-han, a brilliant but emotionally detached engineer who relies solely on logic.

Gu Rumi, a cloud-loving young woman whose name resembles the word for “cloud” in Korean, runs a pension on Ulleungdo Island. She spends her days leisurely gazing at clouds and taking photos, enjoying the slow pace of island life. One day, two handsome men arrive from Seoul at the same time. By chance, they both love clouds as well, and the three quickly hit it off. One of the men has brought along a message videotape that someone left behind ten years earlier as a clue in a treasure hunt. Using the footage as their guide, the three set off around the island searching for treasure—only to find themselves entangled in a love triangle along the way.