Eureka (2000)

ユリイカ

A deadly bus hijacking in rural Kyushu leaves only brother and sister Naoki and Kozue Tamura, and bus driver Makoto Sawai, as survivors. In the aftermath, Makoto abandons his family to wander Japan, and the siblings become mute and dissociated, and are later orphaned. Two years later, Makoto returns and, after failing to reconnect with his family, decides to live with and look after the Tamuras.