Midnight: Stephen Leather

The second book in the Jack Nightingale supernatural thriller series.
Jack Nightingale found it hard enough to save lives when he was a cop. Now he needs to save a soul - his sister`s. But to save her he has to find her and they`ve been separated since birth.
When everyone Jack talks to about his sister dies horribly, he realises that someone, or something, is determined to keep them apart.
If he`s going to save his sister, he`s going to have to do what he does best - negotiate. But any negotiation with the forces of darkness comes at a terrible price. And first Jack must ask himself the question: is every soul worth saving?