In the closing days of World War II, during an air raid in Fukui, young Suwa Oto witnesses her older sister Ineko dancing to the music of bassist Odajima Tatsuji. Ineko, a jazz enthusiast, later attempts suicide by drowning and survives but becomes emotionally hollow. Odajima vanishes. After the war, Oto, now a student, sets out for Tokyo carrying Ineko's double bass on her back, determined to reunite the two. In Tokyo, her singing catches the attention of a performing troupe, and she begins performing on a US military base. There she discovers the troupe's bassist is Odajima himself, but he has lost all memory of his past. The story follows Oto's efforts to restore the connection between her sister and the man who once inspired her, set against the backdrop of post-war Japan under American occupation, a period of rebuilding and cultural upheaval. The narrative explores themes of loss, memory, and the healing power of music.