Jim Butcher's The Dresden Files: Fool Moon #8

Shattered friendships. Fallen allies. Dark family secrets. Oh, and an increasingly large number of mutilated corpses strewn across Chicago. These are merely some of the horrors Harry Dresden has endured in trying to stop an all-out war between several werewolf factions and the enigmatic gangster Johnny Marcone. Now, that war is coming to its tragic conclusion-and Harry will learn that his world, and the powers that threaten all he cares for, are far deadlier than he could possibly imagined...