It's based on a book by Cormac McCarthy. McCarthy has also written 'All the Pretty Horses' and 'No Country for Old Men' which were later adapted into movies. I've read most of his work and 'The Road' is one of his best. It's a very unique story.

I'm excited to see the movie, but the books are always better. McCarthy's writing style is difficult to adjust to(no quotations and almost no commas). But I highly suggest all of his novels.