Ace Books, Mass Market Paperbound, 9780441017980, 292pp.
Publication Date: November 24, 2009
Mason is an enforcer, keeping magical practitioners on the straight and narrow. His ?dog? Louie, is a faithful familiar who's proven over and over that he's a practitioner's best friend. But this time, Louie's in the line of fire when practitioners in San Francisco accidentally unleash a monster into the world.