Gabbie Myers grew up on a ranch in Montana and knew from her first pony that she would become a veterinarian. Now she has a mobile practice that takes her all over the county and sometimes further. When one of the new construction workers at the Lucky Lady Lodge offers to go along for the ride to deliver a horse, she accepts, knowing she's heading into notoriously survivalist territory. She's happy to have someone along who knows one end of a gun from another.

At a truck stop to refuel, Gabbie hears pounding from the inside of an eighteen-wheeler's trailer. The discovery of a teenaged girl inside, leads her and Murdock on a mission to free others trapped in the compound from which the girl escaped.