The Frog unfolds in a secluded forest town, a few hours' drive from Seoul, where Jeon Yeong-ha has spent the last several years. Following his beloved wife's terminal illness, Yeong-ha moved to this tranquil location, fulfilling her dream of living in a beautiful, remote house surrounded by nature. After she died, he chose to remain in the town, residing in a modest home adjacent to the villa he now operates as a holiday rental. His daughter, Ui-seon, frequently urges him to return to Seoul to live with her and her fiancé, but Yeong-ha finds solace in managing the rental alongside his best friend, Yong-chae. However, Yeong-ha lacks the drive to fully commit to the business, relying on Yong-chae to encourage him to promote the property online to attract more guests.