Need help starting my essay!?

I have an outline of everything I need to say, but I need a good introductory sentence in my introduction paragraph, and i'm having writers block. I'm writing about a book called The Road by Cormac McCarthy and it's about a man and son (thats what the book calls them, they are never mentioned by their real names) who try to get to a better place in an apocalyptic setting where many survivors have turned into cannnibals or murderers. All life, trees everything are dead and sunlight is never once mentioned in the novel.