On 9 August, three days after the bombing, Shinji and his father were lying on the floor of a school in a village outside the city, along with dozens of other badly-wounded people, when Shinji’s thoughts turned to a disturbing incident the day before. As he and his father had made their way down from the Toshogu Shrine, two soldiers had barred their way, and told them to go back up the steps - an agonising prospect. When Fukuichi protested, one of the soldiers spat in his face and told him to go to hell. In a society where the elderly were revered, this was deeply shocking, and yet Fukuichi had held in his anger and turned away - staying alive was more important.

It took them hours to make their way out through the back of the shrine, down a slope covered in prickly bushes and the splintered remains of wooden gate-posts. Shinji cursed the soldiers with every painful step.

Shinji just couldn't understand how the soldiers could have treated them like that. Consumed with anger and hatred, he turned to his father for an explanation. "They were demons, weren't they?" he said. "They were evil. Maybe even worse than the American bombers." Fukuichi replied calmly:

 We are in hell right now. No wonder we see demons."

He reminded his son of the angels they had come across - the neighbour who had made them miso soup, Teruo and his crucial intervention, the villagers who were tending to the wounded all around them. Shinji was forced to accept that goodness still existed. He fell asleep that night with tears of relief in his eyes, imagining the face of the Buddha.

Two days later, soldiers came to take Shinji to a field hospital. Father and son had survived for five days wandering together through post-apocalypse Hiroshima, but now they had to part. Fukuichi’s unwavering gaze followed his son as he was carried out to a waiting army truck.

When Shinji arrived in the hospital, the wounds on his leg were now badly infected and needed draining of pus and maggots. His greatest pain, however, came from bed sores caused by days of lying on the ground. One morning, a hospital volunteer noticed him wincing, and promised she would bring him some pillows from home.

The hope he felt at her promise soon turned to anger and despair as he waited all day for her return. "I felt hatred for this woman who had betrayed me so cruelly," he remembers. But she did come back, late in the evening, with the promised pillows - she had been unavoidably delayed. "The moment I saw her, my anger turned to shame," he says. "How could I have been so hateful in my thoughts?"

It was a turning point.

He became determined never to make that mistake again. "She was an angel who had returned to rescue me from my worst pain," he says. "She was also an angel who rescued me from the depths of my own judgmental anger."

One morning, Shinji awoke to an unusual sight - the soldiers at the hospital were no longer wearing their swords. It was 16 August, a week after a second atomic bomb had been dropped on Nagasaki. Japan had surrendered on 14 August. The war had ended.