Proctor John and his men arrive at the dam with Alicia via boat. John talks with Strand about their deal, which John is hesitant to honor. Strand tells Alicia that she needs to trust him.
While hiding out, Nick confronts Madison and berates her for killing Troy. He states that she would probably kill him if she didn't have a choice.
An injured Daniel gives Lola his gun to go help Efrain. When she reaches the control room, she finds that Efrain was killed during the raid on the dam.
Alicia changes John's dressings on his wound, he asks how she knows Strand, to which she replies that he helped their family escape California after the initial outbreak. When he finds out that her mother is Madison, he informs Alicia that her mother is at the dam. He promises her that no harm will come to them if she agrees to be part of their group.
Strand returns to help Madison and Nick escape. Strand is given the detonator while he attempts to smuggle Nick and Madison off disguised as dam workers.
While Strand is walking them out on top of the dam, their plan is jeopardized when Lola appears and begins taking out Proctor John's men, but is eventually killed by Proctor John himself.
Nick, Madison and Strand are taken captive and when John finds out that they are Alicia's family, he says that he's now going to be forced to kill them all.
As they are all walked back to the top of the dam for execution, Strand and Nick bid farewell to each other and embrace. Strand tells Proctor John about the bombs they planted around the dam and that he has the detonator, hoping to use this information as leverage.
When Strand can't find the detonator, Nick reveals to have taken it from him during their embrace moments earlier.
Nick threatens to blow the dam if his family is granted safe passage in a nearby boat.
Madison, Alicia and Strand are allowed to leave and while they attempt to start the boat. Nick tries to hold off as long as he can in order for his family to get a safe enough distance away from the blast. Proctor John's men begin to move in on Nick, but is saved by Walker and Crazy Dog, who begins taking some of his men out.
Eventually Nick has no choice and is forced to blow the dam. The foundation begins to crumble as Daniel catches up to Nick, and they both watch as his family leaves on the boat.
The force of the flood pulls the boat back into the dam and they are all eventually pulled under. While Madison is under the water, she has a hallucination of Travis pulling her out of a grave. She then regains consciousness and swims to the surface.
She makes it to the shore as she watches dozens of people rush to fill up their buckets of the newly released water.