A flashback shows how Ofelia ended up with the Black Hat Reservation. After being found by Jeremiah, he gives her some water but refuses to bring her back with him, as he claims that she has no purpose for "her kind" in his community and leaves her for dead.
As Ofelia continues on in the desert heat, she eventually collapses due to exhaustion and dehydration. She has visions of her father Daniel, pleading with her to remain awake, but she cannot do so.
Suddenly a man on horseback approaches that turns out to be Walker. He takes her back to the Black Hat Reservation and nurses her back to health.
Back in present time, Madison continues to pursue Ofelia and eventually overpowers her, once again holding her prisoner.
The community begins cleaning up the dead in the aftermath of the attack, while a select few remain in dire condition, including Nick. While being interrogated, Ofelia claims she has no idea what the powder was that she used to spike the coffee or that it was going to kill anyone.
Madison takes Ofelia back to the Black Hat Reservation as her hostage and visits Walker. She demands to know what Ofelia used to and threatens to kill her if Walker doesn't comply. Walker states that it was anthrax, with no known cure.
Walker says that Nick will survive due to his age, and that his fight is not with Madison and advises her and her family to leave the ranch. Madison retorts that they have fought to hard and lost too much to get where they are, and are done running. Walker says then they will die.
Ofelia is remorseful for what she has done and scolds Walker for turning her into a killer.
Back at the ranch, Nick recovers quickly. Alycia and Nick express to Madison that they believe they are on the wrong side of the fight against Walker, while Madison says they need to defend the ranch at all costs.
Nick goes to Jeremiah's cabin and rips up the floorboards, revealing skeletal remains buried underneath. After questioning Jeremiah, Nick finds out that Walker's father and uncle were murdered at the hands of Jeremiah.
The ranch discuss how to handle Walker, Alycia comes up with an idea for leverage against him. The ranch infiltrate the Black Hat Reservation and set fires to the community. This provides enough of a distraction for Madison and Alycia to hook Walker's relics trailer to their pickup and drive away with it.
The following day, Walker and Madison meet. After coming to an impasse, and with war imminent, Madison realizes what Walker really wants, Jeremiah's head.
That evening, Madison approaches Jeremiah and tries to get him to make things right. She offers him a gun, hinting that he kill himself to save his people. Jeremiah refuses, as Nick enters. Just as Jeremiah is about to insult him, Nick shoots him in the head. Madison helps stage it as a suicide, as Troy and Jake find their father.
Madison discretely meets Walker and gives him a bag containing Jeremiah's head. He gives Madison a nod, signaling his appreciation for helping him avenge his family and as a sign of peace.
Elsewhere, having escaped the horde of infected at the Rosarito, Strand has been wandering aimlessly just trying to survive. Eventually, he finds the Abigail that was thought to be long lost.
Upon entering, he finds some infected that he quickly dispatches. He throws on his captain's jacket and pops a bottle of champagne, happy to be home.
While scanning radio stations, Strand comes in contact with a man who reveals himself to be a Russian cosmonaut. After finding out that the infection is a global issue, Strand loses hope. The Russian advises that the world does not end until you die, which inspires Strand to move on.
Strand torches the Abigail and continues on with a reinvigorated purpose in life.