Jim Butcher's The Dresden Files- Down Town #4

Yet all of the original tales of the Dresden Files! A few months after the events depicted in Jim Butcher New York Times bestseller The White Night, the war between the Red and the White Council Court rages on. But vampires are not the only supernatural threats only master Chicago employment must resist. Someone unleashed face unlike any Harry had found - and he began orientation innocent, seemingly indiscriminately. Together with his student, Molly Carpenter, Harry must uncover the truth behind this new predator ... no matter how far into the darkness, he must descend.