This isn't a movie about war or its aftermath. It's about a child watching his mother die slowly while scrounging metal in the ruins, and understanding there's nothing he can do to stop it. Gen keeps moving because he has to, because his friends are starving, because staying alive is the only rebellion left. The film never turns suffering into nobility or survival into triumph. It just watches a kid be a kid in a place where childhood ended three years ago, and that refusal to make it mean something larger is what breaks you.

Three years after the atomic bomb reduced Hiroshima to ash, Gen is a fourth-grader picking through ruins for scrap metal to feed his family. His mother's health deteriorates as radiation sickness takes hold. Trade has returned to the city, but survival remains a constant struggle for those left behind. When Gen and his adopted brother Ryuta meet a group of homeless orphans, led by a tough older boy and including a girl still marked by burn scars from the day of the bombing, Gen realizes how fortunate he is in many ways. An old man suffering from depression joins their circle, and together they form a makeshift family, supporting one another. When a typhoon floods the orphans' home, Gen helps them build a new one on abandoned land. But reality stays harsh: many orphans die alone, and reminders of the bomb are everywhere.