The spring Seo Dal-mi lost everything, Nam Do-san's letters kept her company. Fifteen years later, she needs him by her side to prove Won In-jae wrong.

Despite differing pasts, Dal-mi and In-jae fight for their dreams at the same starting line. Ji-pyeong sets out to protect Dal-mi and help Do-san.

Do-san and Dal-mi envision new goals for their future. Ji-pyeong finds a way to pay forward his gratitude for Won-deok. In-jae returns to her roots.