The Dresden Files: Storm Front

We are introduced to Harry Dresden, private detective and practicing wizard. When he tries to help the Chicago Police Department solve a grisly murder, he finds himself the target of a homicidal magician. And as if that isn't bad enough, the High Council of wizards begins to think that he is falling to the dark side, so he must elude them as well. Now he must stop the murderer and clear his name before his time runs out.