The fourth season of The Walking Dead finds Rick Grimes (Andrew Lincoln) desperate to rediscover his own humanity and preserve what he can of his son Carl's (Chandler Riggs) childhood through reinventing himself as a farmer while a counsel including Carol (Melissa McBride) and Daryl (Norman Reedus) in addition to several Woodbury ex-pats take on leadership roles. His newfound sense of peace is quickly derailed, however, when a mysterious illness begins to decimate the community. Elsewhere, the disgraced Governor (David Morrissey) roams the apocalyptic streets on his own until happening upon a family of survivors who reignite both his will to survive and take revenge against Rick, who he blames for the loss of Woodbury. Following a massacre at the prison, the group is splintered into several factions, none of whom can be sure about the fates of the others, and forced to find shelter among a population of survivors that can pose as much and often more of a threat than the walkers themselves.

After leaving his LAPD narcotics post following a bungled operation that left him wracked with remorse and regret, Sheriff Ray Owens (Schwarzenegger) moved out of Los Angeles and settled into a life fighting what little crime takes place in sleepy border town Somerton Junction. But that peaceful existence is shattered when Gabriel Cortez (Eduardo Noriega), the most notorious, wanted drug kingpin in the western hemisphere, makes a deadly yet spectacular escape from an FBI prisoner convoy. With the help of a fierce band of lawless mercenaries led by the icy Burrell (Peter Stormare), Cortez begins racing towards the US-Mexico border at 250 mph in a specially-outfitted Corvette ZR1 with a hostage in tow. Cortez path straight through Summerton Junction, where the whole of the U.S. law enforcement, including Agent John Bannister (Forest Whitaker) will have their final opportunity to intercept him before the violent fugitive slips across the border forever. At first reluctant to become involved, and then counted out because of the perceived ineptitude of his small town force, Owens ultimately rallies his team and takes the matter into his own hands, setting the stage for a classic showdown.