On what begins as a quiet morning in southwest Japan, a crazed killer, apparently without motive, hijacks a city bus. In the ensuing carnage only three people survive--the driver, a schoolgirl and her older brother. After a long period away, the traumatized bus driver, Makoto, returns to his family only to find his wife has left him. The two siblings, Kozue and Naoki, have withdrawn further into silence since their mother left home to begin a new life and their father died in a car accident. Upon Makota's return to town, he reacquaints, himself with the orphaned children, Kozue and Naoki who are living alone in their family home. He moves into their house--filthy from neglect--and together with the orphans' cousin, a college student on vacation, they form a kind of quasi-family.