Returning from the memorial service of her fiance -- who's been dead for two years -- Hiroko Watanabe relives the past by thumbing through his old yearbook. Missing her fiance Itsuki Fujii, Hiroko sends him a letter to an address she finds in the book. She mysteriously gets a response, not from him, but from his schoolmate, a young woman also named Itsuki Fujii. From this coincidence begins a long-distance friendship between these two women who write letters to each other, sharing memories and cherished times. In the end, some new truths are revealed about themselves and about the man they thought they knew.