Classified K-9 Unit is this year's linked series of romantic suspense stories involving highly trained police dogs and their handlers. I have enjoyed all the previous books so I'm looking forward to this crop. Terri Reed starts us off with a crime story set in mountain country. GUARDIAN features FBI agent Leo Gallagher and his trusty K-9 partner True, a chocolate Labrador.

Alicia Duncan is enjoying visiting a lake in Wyoming when she sees a woman's body being dumped in the water. She has to flee with her young son Charlie before the criminal gets a clear shot at her. When she reports the crime, a special FBI unit in Montana is notified. Leo takes the assignment as his True is trained for water search as well as air scent tracking. The unit suspect that this crime may be linked to a recent gangland arrest gone wrong, which resulted in one of their unit being kidnapped. The dead woman could be a witness who had agreed to testify.

I have previously read about an Irish mountain rescue dog trainer who taught himself how to teach his dogs to identify the scent of a body under water. Here I see a good account of the technique, with a diver to do the underwater work. Not long after, Leo has escorted Alicia and Charlie home and is securing the area when a quadcopter drone buzzes over the house. Someone wants to find and eliminate the witness. Alicia, a teacher, is widowed and is determined not to get mixed up with any more police officers like her late husband. Her elderly father agrees. Leo's not sure what went wrong, but he thinks the little family deserves all the protection he can give them.

I like the vivid descriptions of the natural environment and how it can make searches slower. On one search a yellow Lab pup is found hiding in bushes - his lady owner has been killed. This is a sobering reminder that although we've seen explosions, fires and dangerous driving, most of the characters in this suspense story are ordinary people living usual lives. I can heartily recommend GUARDIAN to anyone who enjoys a suspenseful romance story. The relationship develops slowly and can be read by anyone from teens to adults. Trust Terri Reed to give us a romance in which the dogs wear Kevlar jackets. I'll look out for the rest of the series, with Sheriff followed by Special Agent next in line.