The US Army dropped a nuclear bomb on the city of Hiroshima which killed about 100,000 people and at least that same amount was hurt and the book follows six survivors many people that survived was too hurt to get moved and there wasn't any official help people end up sick even from the radiation and for weeks and weeks they are sick still with no help. the results was far from over in the end and the issues continue for pretty much ever not just for the area but for the whole world.