Business has been slow for Harry Dresden — slow enough that Chicago's only professional wizard, the sole entry of his kind in the phone book, can't reliably afford dinner. Then a body turns up at a half-finished nightclub belonging to crime boss Gentleman Johnny Marcone: savagely mauled, ringed by animal tracks, and killed under a full moon.
Karrin Murphy of Chicago PD's Special Investigations brings Harry in as a consultant on what she calls the Lobo killings. What he finds is not a werewolf but several kinds of them, each with its own rules, its own weaknesses and its own reasons — one of them an inherited curse said to run back to the time of Saint Patrick, and killable only with silver handed down through a family. Pinned between skeptical federal agents, a shape-shifting biker gang, a threatened mobster and a police force fast losing patience with him, Harry has until the next moonrise to work out which monster is doing the killing.
Fool Moon is the second novel of Jim Butcher's Dresden Files, the hardboiled detective series in which the private eye happens to be a wizard.