There was nuclear war and everything burned. Except not quite everything – some people and buildings survived. Close enough though. Thick layers of ash cover everything on the planet; presumably all plants and therefore animals perished. The survivors that are left resort to scrounging around for hidden caches of canned food (either left over from before the disaster or stockpiled by another survivor) or cannibalism. Kind of depressing, no? It’s a dog-eat-dog world, literally. Well, people-eat-people. When the means of production are completely wiped out, what else is left? Quite a horrible, hopeless way to live.
After several years and for unexplained reasons, a man and his son set out on a journey following one of the old roads – probably a highway. Pretty much everyone they encounter is a thief, cannibal, or other scumbag who wants to steal their stuff and eat them. (I guess all the good people have been eaten already!) Somehow in spite of the utter hopelessness around him, the boy has an optimistic spirit — he always wants to help people, even though nobody has ever helped them. (But his father has certainly helped the boy; maybe that’s where he gets it from.) The father struggles with the boy’s desire to give away supplies or otherwise endanger their security by helping others. What’s the greater good, helping others or protecting family? Hard to say, but I think most parents would side with the father in this story.
Luckily there’s a happy ending. The father dies, but the boy ends up with the first other good folk we meet in the book.