Nightfall - Stephen Leather

'You're going to hell, Jack Nightingale': They are words that ended his career as a police negotiator. Now Jack's a struggling private detective - and the chilling words come back to haunt him.

Nightingale's life is turned upside down the day that he inherits a mansion with a priceless library; it comes from a man who claims to be his father, and it comes with a warning. That Nightingale's soul was sold at birth and a devil will come to claim it on his thirty-third birthday - just three weeks away.

Jack doesn't believe in Hell, probably doesn't believe in Heaven either. But when people close to him start to die horribly, he is led to the inescapable conclusion that real evil may be at work. And that if he doesn't find a way out he'll be damned in hell for eternity.