A Darkness More Than Night is a title I have wanted to use for many years but waited until I had the right story. The title comes from Raymond Chandler, writer of several classic detective novels set in Los Angeles.

Once while writing about what made his early hardboiled stories so popular he stated that, among other things, it was because in these stories the "streets were alive with a darkness that was more than night." I read that a long time ago and it always stuck with me. It occurred to me while writing my tenth book that this was the story for which that title was made.

In this book my plan was to make the story an exploration of Harry Bosch's character and the cost of his going into the darkness. By darkness, I mean the underworld of crime and moral corruption where he toils as a cop.

The philosopher Friedrich Nietzsche once wrote that when you look into the darkness of the abyss that the abyss looks into you. Probably no other line or thought more inspires or informs my work.

By virtue of his job as a police detective, Harry Bosch has spent most of his life looking into the abyss, into the darkness of the human soul. What has this cost him? What did going into the darkness do to him? These questions became the basis of this book.

To me, this book is a study of the price that is paid by those in our society who must go into the darkness to right wrongs and solve the crimes of the morally corrupt.

At one point a character in the book takes a basic law of physics - for every action there is an equal and opposite reaction-and adopts it to human or spiritual physics, concluding that you can't go into the darkness without changing it and yourself. If that conclusion is correct, then Harry Bosch's years of carrying a badge have had an unseen cost attached. Exactly what that is forms the exploration of A Darkness More Than Night.

Because all of the prior books about Harry Bosch have been constructed so that the world is seen through his eyes, my goal with this book was to change that a bit. There are many sections of the book where this is still the case.

But the majority of the book is seen through another character's eyes - Terry McCaleb, who I brought back from the novel Blood Work. In Darkness we get a view of Bosch and his world through McCaleb's eyes.

This allowed me to reveal things about him that would have been awkward or even impossible in the prior Bosch books. I think it allows the reader a different view of Harry. My hope is that the reader will be surprised by what they see from this new angle.