Wyoming game warden Joe Pickett confronts drug cartel killers hunting on his turf in the nineteenth installment of the US crime series. Wyoming game warden Joe Pickett encounters bad behavior on his own turf: a drone is killing wildlife – and the drone belongs to a mysterious and wealthy man whose grandson is dating Joe's own daughter, Lucy. When Joe tries to lay down the rules for the drone operator, he is asked by the FBI and the DOJ to stand down – and with good reason: the man is in the witness relocation program and he's being hunted by four killers from the Sinaloa cartel. If Joe isn't careful, his actions will expose the witness to his pursuers. Teaming up with a new partner – a female game warden – to confront these assassins, Joe finds himself their prey – along with Lucy and her boyfriend.