In Kyushu, Japan, a hijacked bus leaves only three survivors: driver Makoto, schoolgirl Kozue, and her brother Naoki. Traumatized, Makoto vanishes. Two years later, after their parents' separation and father's death, the siblings live alone. Makoto returns, joined by cousin Akihiko. When a murder occurs, suspicions fall on Makoto. He buys an old bus, turning it into living quarters, and proposes a trip to the three youths.