On a rainy day in summer, girl Kim Tae Hee (played by Lee Eun Joo) walked into the umbrella of boy Seo In Woo (played by Lee Byung Hun) to take shelter from the rain. The boy fell in love with her at first sight. The relationship between the two gradually warmed up in college. On a rainy night, the two quarreled and reconciled, and their relationship was too strong to be resolved. The night before Ren You's military service, he didn't wait for his wife who agreed to come to see him off...