Young Gen Nakaoka lives in Hiroshima after the dropping of the nuclear bomb. His father and siblings died and he lives with his mother and his new prematurely born sister Tomoko. Gen tries to earn money for the family and works looking after a burnt victim, Seiji, who is an artist who lost the will to live because he can no longer draw and paint due to his wounds. They develop a friendship and Gen helps Seiji draw with his teeth, but Seiji ultimately dies. On August 14th Emperor Hirohito announces Japans defeat. American soldiers come to help rebuilding Japan. Gen initialy fears the enemy but soon realizes they are not as bad as he thought, although he sometimes witnesses soldiers harvesting organs for medical purpose.