The Revolution season finale was a bombshell! Grace was explaining to Aaron and Rachel what could possible occur if the power was turned back on. Dan told Rachel and Aaron if they tried to turn on the power he would kill them. Aaron was going through a computer and realized that his operating system, which he created in MIT was The Tower's operating system. MIT sold Aaron's code to the D.O.D. While browsing the computer Aaron realized that he had written a back door in the code, and he thought that someone intentionally caused the black out.
Meanwhile, Randall went into the safe room where Rachel and Monroe were in the last episode, smashed a picture frame of George W. Bush Jr. and inside was a key card for the facility. Rachel wanted the power back so she faked being ill in the infirmary and chloroformed Grace. She took the unconscious Grace's key card. Miles and Monroe were about to shoot each other but some of Dan's troops found them and Miles and Monroe teamed up to fend them off. They were chased into a water waste section of The Tower and flushed out through a drain. Nora wasn't and found Charlie, Rachel, and Aaron. They went toward level 12 using the key card. Dan and his men pursued them and tried to kill them. Nora set a booby trap in the hallway, but Dan saw it. His men and him stepped over the trip wire. But Nora threw a fire extinguisher at the wire to trip it and set off the explosion. Sadly, she was injured by the blast, she had shrapnel in stomach. Aaron, Charlie and Rachel dragged her to a side room. Rachel wanted to leave Nora. Charlie protested, but Rachel went despite Nora's condition. She and Aaron left for level 12 and Charlie stayed with Nora.
Monroe and Miles ended up on land and they began fighting. Until a Monroe troop fired at them. Monroe was taken captive back to the camp outside the Tower. Tom was the acting leader of the camp. Tom told Monroe he isn't going to kill him, rather have a mock trial, to present the illusion of justice. Because unlike Monroe he knew how to play people, instead of using just brute force and fear.
Tom left Monroe tied up and went to investigate the hole they blew into The Tower's entrance doors. Miles showed up at the the tent where Monroe was captured. Monroe, in shock, stared at Miles. Miles spoke, and told Monroe that he should stop asking why he tried to kill him. He should rather ask the more important question, which is why Miles couldn't kill him. Miles told Monroe he couldn't kill him because they are brothers (not biological, just in bond). He cut Monroe's bonds, freeing him. He then told Monroe to run. Monroe confused asked, "what?" Miles told him to run, then shouted that Monroe was escaping. During the chaos he snuck back into The Tower through the hole Tom Neville and his troops made. Miles then found Charlie and Nora. Miles didn't want Nora to die. Him and Charlie took Nora to the Tower's infirmary. But Nora died in Miles' arms.
Rachel. Aaron, Miles and Charlie all met up at level 12. They got into a fire fight with Neville's troops, they retreated into the control room and locked them out. Aaron turned on the power. The scene skipped to different places with the power going on and people's responses. The group then saw Randall inside a room adjacent to their part of the control room. Randall launched two ICBMs at Georgia and Philadelphia. Randall said that the nation needed to be rebuilt and that a house divided cannot stand, and said that he was a patriot, then he killed himself.
The scene cut to to a man saying "Sir, Randall Flynn did it. "it's time to go home, Mr. President."" The camera paned out to reveal Guantanamo Bay, a U.S. Colony and a silhouette of a man in the window.