Three years after the bombing of Hiroshima, Gen is now a fourth‑grade student. The city remains in ruins, and he scavenges scrap metal to provide food for himself and his dwindling family, though trade has slowly resumed. As his mother slowly succumbs to radiation‑induced illness, Gen and his friend Ryuta bond with a group of orphans led by a tough‑nosed older child, including a girl who still bears burn scars from the blast. An elderly man battling depression also joins the group, and together they create a makeshift family, supporting one another amid harsh realities. Yet many of the orphans still die alone, and the grim reminders of the catastrophe linger everywhere.