When a friend is wrongly convicted, Deputy Marshal Mason Raines must take his place in a gunfighting competition unlike any other. To survive, he must overcome a handful of unique shooting challenges, each with deadly consequences. As Mason defeats one ruthless competitor after another, he begins to question not only the brutality of the competition but also the guilt of its competitors.

Meanwhile, Tanner and Samantha embark on a cross-country journey to find Issa. Along the way, they take up the cause of a cantankerous old nun searching for her missing sisters. Their journey leads them to a sadistic doctor specializing in eugenics, and an abandoned children's insane asylum with a dark inhabitant.

Only a handful of miles away, Issa leads a band of infected misfits on a bold rescue mission. While attempting to overcome a community of violent slavers, tragedy strikes, and she is forced accept that the fight cannot be won. Trapped and outnumbered, Issa and those in her charge begin to wonder if there is any hope of escape.