Mastiff (Beka Cooper)

is book #3 of The Legend of Beka Cooper.
==Book Description==
This is the third book in the Beka Cooper trilogy, and Beka is a full-fledged Dog now, but it hasn't made her job with the law-enforcing Provost's Guard any easier. On this hunt, she'll need all her resources, from her bare-knuckled fighting skills to her suspiciously intelligent cat, Pounce.
(Description from amazon.com)