Damnation Street by Andrew Klavan
Scott Weiss is a middle-aged private eye based in San Francisco, an ex-cop with a basset hound's face, a romantic's soul and an empath's ability to read others. He's holed up in a hotel room, thinking of the girl he should have left alone and waiting for the Shadowman, the hitman he knows is stalking him. Jim Bishop is a young, good-looking livewire with a taste for violence, drugs and loose women. Bishop is holed up too, three-days-drunk with the blonde who nearly killed him on his mind and the cops on his tail. Bishop used to work for Weiss until he screwed him over for stolen cash and a couple of hook-ups with his killer girlfriend. Now, he is Weiss's only hope as his ex-employer heads towards an almost certainly fatal confrontation with the Shadowman. Determined to redeem himself, Bishop needs to find the elusive killer before he finds Weiss...With its sinuous plot, gritty dialogue and sheer drive, Damnation Street excels in every measurable category; it's Andrew Klavan at his best.