Harper. The K9 Files, #19

With his surgery postponed, Harper can finally take on a War Dog case to help out Kat and Badger. Harper knows it is short-term, a fill-his-time thing. Considering his stage of life, that is perfect. Finding out he needs to find two dogs is a surprise, but he doesn't expect to track one dog in order to keep another alive. As Saffron works to keep Beauty alive, she knows how important it is to find Beauty's bonded partner, Beast.
The pair of dogs had come to Saffron for medical treatment. Beast had thereafter been released, supposedly taken to a huge training facility, while Beauty hadn't been healthy enough to leave Saffron's care. Finding Harper on Beast's trail is both a relief and a distraction. Saffron can't ignore the dynamic Harper, even as injured and as scarred as he is. Not to mention the work he's doing is so close to her own. As Harper gets closer to Beast's location, it becomes obvious that someone wants to make sure the War Dog doesn't reach his destination.
But why? And how far would this person go to take down the dog?