The Kite Runner, by Khaled Hosseini, is the story of two brothers: the privileged Amir (who is not aware for some time that he has a brother) and his loyal childhood friend (and brother), Hassan. Amir narrates the story as an adult, and he shares his experiences with Hassan and others with an adult's understanding.
In chapter twenty, Amir returns to Kabul for the first time since he left his home city many years before, and virtually nothing is the same. His idyllic world has been replaced with beggars, destruction, and the Taliban. There is little evidence of the town he once knew. Amir has an interesting encounter with a beggar who once taught with Amir's mother at the university; from him he learns precious information about the mother who died when he was born. Finally Amir makes his way to the orphanage where he hopes to find Hassan's son, Sohrab. Instead he finds that Sohrab has be "sold" to a Taliban official in exchange for money, which the director needs to help the other children.
There is nothing extraordinary about the structure of this chapter compared with the rest of the novel; however, it is conspicuously full of contrasts between the Kabul of Amir's childhood and Kabul under Taliban control. We know the streets used to smell of lamb kabobs but are now thick with the smell of diesel fuel; we know that a man who used to be a university professor has been reduced to begging on the streets; and we know that where happy families used to walk tree-lined streets there are now only husbandless women and fatherless children begging on the treeless streets.
All of this leads directly to Amir's outrage and determination to rescue Sohrab, an act which changes both their lives forever.