Part of the Texas K9 series, set in the town of Sagebrush, GUARD DUTY features Valerie Salgado with her Rottweiler Lexi. Crime has been escalating and every corner store robbery carries a frisson of fear for the responders. Valerie sets her dog to track the latest armed robbers and follows but when her dog leaps a fence in hot pursuit and someone throws a crate off a roof at Valerie, an FBI agent shows up and helps her to apprehend the climber while well-trained Lexi gets the other man.

Agent Trevor Lewis is in search of a bank robber who grew up in Sagebrush, and he's willing to work with the locals. He doesn't expect to spot his quarry on his first day with Valerie. They lose the man, but Trevor is all the more determined to track him down. However their work is complicated by that fact that Valerie, who cares for her young niece, is receiving death threats.

Family dynamics come to the fore in GUARD DUTY as Valerie has a brother who works undercover and a retired detective father who pushes her to take detective exams and give up the K9 work which she loves. The fugitive also has a half- sister and any family may be his point of contact with the area, so Trevor has to work on that presumption. But the officers here know all too well that dogs are not invulnerable, and the organised crime syndicate gets more vicious by the day.

Sharon Dunn has given us a fast-moving, busy, well- researched drama with an element of romance, in which the canines take a major role. GUARD DUTY is a great addition to the series and shows how a reliable K9 is an asset to any law enforcement unit.