Critical Damage — Robert K. Lewis

When ex-cop and recovering junkie Mark Mallen is asked to track down two very different girls who have gone missing, he doesn't think twice about putting himself in harm's way to find them. Bloodied and bruised, Mallen shakes down the pimps and hustlers who could crack the cases wide open, leaving no stone unturned in San Francisco's criminal underground.

But something isn't right. Somebody's trying to scare Mallen off, and it's no ordinary street thug. With heat coming at him from all angles, Mallen's search for the truth leads him to men who will stop at nothing to make sure their twisted desires never see the light of day.