Yoon-Hee lives with her teenage daughter Sae-Bom. On a winter day, Yoon-Hee receives a letter from Otaru, Japan. Sae-Bom accidentally reads the letter and learns about her mother's first love, which she never spoke about before.

Atsushi is a civic construction worker who was widowed following a random murder. Toko's husband is neither interested in her nor in how his mother treats his wife. Shinomiya is a lawyer whose homosexuality has lead to...