The fast-paced, action-packed career of the US Marshal's rising star K9 team-Deputy Marshal Caitlyn Reed and her dog, Renegade-turns toward the tranquil rolling hills of Tennessee, when Caitlyn is assigned to oversee a racehorse barn recently seized by the Marshals Service. The job seems like vacation duty until several high-dollar horses go missing, shots are fired, and Renegade's life hangs in the balance. Caitlyn's new husband, Sheriff Colt Branson, is back at home in Wyoming assimilating to his new role as a father and tending to the seemingly mundane duties of a small-town sheriff. But things heat up when local cattle mysteriously die, and a simple traffic stop turns deadly. When Caitlyn chases the horse thieves into the seedy underbelly of the racing world, she tracks the roots of corruption all the way to the streets of New York City. In Moose Creek, Colt uncovers a surprising connection to Caitlyn's case. The question remains, will they all survive the unravelling of this twisted conspiracy, or will darkness ultimately prevail?