Based on the context and the answer, generate a question. 

Context: It 's not because it 's post - apocalyptic because that 's what drew me to it . Ordinarily , I would not keep reading such a depressing book . McCarthy did a excellent job of taking me from one emotional extreme to the other , however .

Answer:

It caused the reader 's feeling to go through a rollercoaster .



What may the author achieve with the book ?