Now inside the tower, Rachel tries to convince her former colleagues Dan and Grace to turn on the power. They adamantly refuse leaving it up to her, Nora, Charlie and Aaron to act on their own. Miles and Monroes also face off in the tower but old friendships seemingly die hard. Outside the tower, Neville has taken command of Monroe's troops and wants to solidify his position by ensuring the power stays off. Aaron, Nora, Rachel and Charlie - now joined by Miles - make it to the 12th floor but one of them will not survive. Aaron believes he can turn the power on but Randall has also made it to the 12th floor and has planned something quite unexpected.
As the Rebels infiltrate the tower, Rachel and Aaron try to convince Dan and Grace to let them turn the power back on.
- Open with Monroe and Miles pointing guns at one another. They end up teaming up to shoot their way out of danger and flee with Nora to a tunnel filled with rushing water. They fall in and we see Nora is able to grab onto something.
Randall finds a hidden key card behind a framed photo.
Aaron asks for an explanation as the danger of turning the power back on. Grace says they simply don't know what will happen. Rachel is warned that if her group tries to make it to Level 12 they'll be killed.
Tom kills Franklin and places a gun in his hand to pretend it was an act of self-defense.
Miles wakes up on a beach and immediately Monroe starts pummeling him. They fight until someone in a militia uniform starts shooting at them. This allows Miles to flee.
We flash to ten years after the blackout with Miles and Monroe sharing some drinks and memories. An explosion goes off and both men are knocked to the floor.
After some snooping on the Tower's computer Aaron finds a code he wrote when he was in college. Without knowing it Aaron wrote the Tower's operating system. Grace tells him that Ben found him on purpose.
Tom tells Jason they need to stop Rachel from turning the lights on. He tells his son they need to put their personal differences behind them. Jason's request is that Charlie and Rachel are left alive. They are informed Monroe is nearby.
Rachel tells Grace the militia must be stopped, in part so her son doesn't die for nothing. She tells Grace the chance of everybody dying is one in a billion but Grace still says no. Rachel then covers her with a napkin and knocks her unconscious. She grabs her key card and tells Charlie and Aaron "let's go."
While staggering through the woods Miles thinks back to recovering from the bomb blast ten years earlier. It was a U.S. rebel bomber and Monroe tells Miles he's killed the man's wife and three children to make an example of him.
Aaron tells Rachel there is a virtual backdoor in his code. He thinks the blackout was done intentionally.
Monroe and Miles continue their fight. Miles knocks him down and walks away, saying they have more important problems then kicking each other's butt. The two start rehashing their divide. Monroe says everything he's done was for Miles. A helicopter approaches and opens fire. A Monroe militia soldier knocks Monroe out with his rifle.
Nora tells Rachel she knows she loves Miles. She tells her that Miles loves her.
The stairwell to level 12 is heavily guarded. Nora has an idea.
Monroe is brought to Tom who tells him "there's been a change in management." Monroe tells Tom he's going to have him and his wife killed. Tom's response is that he's lost his mind and has a "borderline erotic" fixation on Miles. The plan is for Monroe to stand trial.
A trip wire, explosive and well-thrown fire extinguisher is enough to take out the guards at level 11. But Nora appears to be badly injured.
Miles takes out the men guarding Monroe and cuts off his handcuffs. He tells Monroe "we're still brothers," something which will never change. He tells Monroe to run.
Grace wakes up but runs right into Tom and his men.
While working on Nora Rachel notices that the militia has arrived. It basically comes down to a decision between saving Nora's life or turning on the life. Charlie wants to take Nora to the infirmary, but Rachel thinks the priority is turning on the lights. Charlie pleads with Rachel to help Nora but her mother says no. She takes Aaron with her and leaves Charlie to help Nora. A militia soldier hears Nora and knocks down the door. He begins choking Charlie until Miles arrives to save the day. Miles attempts to carry Nora to medical assistance but she dies in the hallway.
Tom and his men appear to have Rachel and Aaron stopped. But Miles arrives and helps take most of them out. Rachel, Charlie Aaron and Miles are able to get into the level 12 Command Center and lock the door behind them. While Tom searches for a way in Aaron enters the code and turns on the world's lights.
Immediately plans are made in Georgia to go after the militia.
To everyone's horror Randall has locked himself in a different part of the Command Center. He tells Rachel he wanted he to turn on the power so he could launch nuclear weapons. He sends ICBMs towards Atlanta and Philadelphia, then shoots himself in the head.
We see that the US President has been hold up in Guantanamo Bay. He's told "Randall did it" and "it's time to go home."