The plot takes a devastating turn when Suzu and her young niece, Harumi, are caught in the explosion of a delayed-action bomb. Harumi is killed instantly, and Suzu's right hand—her drawing hand—is lost. This event marks the end of Suzu's innocence. Her art, once a source of joy and a way to beautify the world, is taken from her, forcing her to confront the grim reality of her situation without her primary coping mechanism.
The climax of the film coincides with the atomic bombing of Hiroshima on August 6, 1945. Suzu witnesses the horrifying mushroom cloud from Kure, a moment that is chilling in its quiet distance. She later learns that her parents were killed in the bombing, and her sister, Sumi, is suffering from radiation sickness. The Emperor's subsequent announcement of Japan's surrender sends Suzu into a rage, not out of nationalism, but out of a feeling that all their suffering and sacrifices were for nothing.
The ending, however, is one of quiet hope. As Suzu and Shusaku walk through the ruins of Hiroshima, they find a young girl orphaned by the bombing. Without hesitation, they take her in as their own. This act of compassion symbolizes the beginning of a new family and the resilience of the human spirit to rebuild and find love even in the ashes of destruction. The final scenes show the young girl growing up in the Hojo household, with Suzu, now adapted to life with one hand, helping her sew. It signifies that life, though irrevocably changed, goes on.