The Last Dogs: Journey's End (The Last Dogs, 4)

Canine heroes Max, Rocky, and Gizmo return in this exciting series finale! As the trio travel south, following a trail of beacons left by Dr. Lynn, they encounter a stampede of horses. The horses urge the dogs to turn back, warning about a "silver wall of doom" that lies ahead.
But the warning only serves to motivate Max. Could this be the wall from his dreams? The wall keeping Max from his family? Helped by animals along the way -- including bats and armadillos -- the dogs find themselves deep in the desert, where they face a new enemy: coyotes. They aren't the only danger, though. Dolph and his wolf pack lie in wait -- poised for a final showdown.
The Last Dogs: Journey's End is the final book in a thrilling series about three unlikely friends on an epic quest to find their people -- and bring them home.