Cormac McCarthy's The Road begins in medias res ("in the middle of things") but after the apocalypse ("series of low concussions"). The novel borrows narrative elements from science fiction, travelogue, horror, and bildungsroman (novel of education). The narrative structure is, more or less, a walking Socratic seminar--a series of questions (by the son) and answers (by the father). Irony is achieved in the seriousness of the son's wanting to know that they're "the good guys" and the father's patient reassurance that they are. The father must not only protect the boy's life, but--more importantly--his faith and innocence.
Action is determined by the father's two bullets. He must decide whether to shoot a cannibal or kill himself and his son to avoid being eaten. Worse, he has taught the boy to use the gun on himself, an unthinkable act. Death is inevitable for the father, we know, so we are desperately vested in the safety of the son's life. He is like Adam, Jesus, and the Holy Grail: the world's faith and future generations depend on his survival.
Even though the narration is told in third person, it is clearly from the father's point of view. We know about his bad dreams, and he has flashbacks about his wife. The time is present day or future, hard to tell. The father says he hasn't kept a calendar in years. We do know that the boy was born into the apocalypse--he has no memories before it. We also know that his mother abandoned them by committing suicide. And we know that the father will likely die from inhaling the foul air from the fallout. So, the father must help the son find a sense of hope and faith in a nuclear winter filled with cannibals.
About half-way through the novel, McCarthy foreshadows his ending when the boy thinks he sees another boy. In the end, after the father dies and boy is rescued by the man with the shotgun, we realize that this other family has been following the father and son the entire novel.
The turning point of the novel, however, is the son's decision to go back onto the road. The father, had he been alive would not have done this, and he had taught the boy to hide at all costs. The son's act of faith in confronting the man with the shotgun leads to his and humanity's salvation--although, technically, the ending is open-ended and salvation is implicit.