35-year-old architect Seung-Min receives a visit at his office from a woman. Seung-Min doesn’t recognize the woman at first, but then realizes the woman is Seo-Yeon. Seo-Yeon is his first love, but he hasn’t seen her since his freshman year in college. Seo-Yeon now has a request. She wants to hire Seung-Min to rebuild her home on Jeju Island. 15 years ago, Seung-Min is a naive young man beginning his architecture studies in college. He first meets Seo-Yeon in his Architecture 101 class. As they work on a class project together, Seung-Min and Seo-Yeon begin to fall in love. Back to the present day, Seung-Min is hesitant to take Seo-Yeon’s job offer. Seo-Yeon persists and even goes to his boss with her wish. Seung-Min now has no choice, but to take on Seo-Yeon’s home project. Old memories of love and heartbreak will soon resurface, as they find themselves at different junctions in their lives.