The episode begins and everyone had gathered outside The Tower, desperate to get inside and find out how to control the power-sucking nanites. Rachel though, had a different motive. She only wants to kill Monroe, as revenge for the death of her son. So, she snuck into Monroe’s tent and dropped a hand grenade. Somehow, Monroe’s guards manage to get both him and Rachel clear of the blast as the grenade goes off. Meanwhile, Miles and his crew of Charlie, Nora, Tom Neville, and Jason Neville all arrive in their stolen helicopter. They are just a couple miles from the Tower and are headed that way. Monroe gets Rachel to open the door to The Tower.
Her handprint works to open the doors while Flynn’s did not. As they walk along the corridors, Rachel and Flynn talk. He can’t figure out how she got the doors to open. Rachel doesn’t know either. Flynn figures Grace must have done it. He’s wrong though as it is soon seen the mysterious people inside the Tower watching everything on their TV monitors. They close the doors to The Tower, sealing Monroe’s army outside and Monroe inside. Miles and company arrive at the site. A few moments later, they find Aaron. Inside, Flynn shows Monroe some of the capabilities of the Tower, including a vast array of satellites the facility can access that are still in use orbiting the planet. Flynn tells Monroe that they need to get to Level 12 to control everything. Rachel looks worried.
Monroe, Flynn, Rachel and a few soldiers take the elevator down to 12. But, it stops on 11 and they are ambushed. Monroe’s men are blown to bits, but Rachel and Monroe escape into a sealed room. Outside, Jason and Tom Neville blow up the power generator that Monroe’s men are using, causing all the lights in the area to go out. This allows Miles, Aaron, Nora, and Charlie the time to open the tower door. But, a firefight soon erupts. Jason and Tom are stuck outside and cannot get in. Charlie looks on as her boyfriend, Jason, is separated from her. Inside the sealed room, Rachel tells Monroe she has no idea who the people who ambushed them are. She says she knows nothing about what is going on, but Monroe thinks she is lying. She makes it clear that all she cares about is killing Monroe.
She claims she does not even care about living herself. He thinks she still cares, at least a little bit, about living. Flashback to a week before the blackout; Rachel and her husband, Ben, are talking about how dangerous it will be to test the Tower. Rachel doesn’t want to do it. She looks at the special power medallions and worries they might need to use them. She and Ben fight about it a bit and she suggests they spend some time apart. Back in the present, the leader of Monroe’s men on the outside, Franklin, and his right-hand man, Reilly, are questioning Tom and Jason Neville. Franklin wants Neville to get him into the Tower.
Neville says nothing, but talks about how crazy Monroe has become and implies that Monroe will soon turn on Franklin and Reilly the way he once turned on Neville. Miles, Charlie, and everyone else get down to level 11, where they see all of Monroe’s people have been massacred. Aaron notices the other elevator is on the move. Someone is coming he concludes. They don’t wait to see who it is, fleeing to a nearby laboratory room. Aaron sees something that bothers him in the room, but before he can investigate, the people outside the door start to blast their way in so Miles and everyone else flee through an air duct. In their hiding place, Monroe and Rachel are having some deep conversations. Monroe seems to come to grips with all the blood he has spilled.
He tells Rachel about the son he has never met. Flashback to 4 months after the blackout; Ben has rigged a computer and is using his power medallion to try to contact someone. Rachel comes in and is despondent over all the death their invention has caused. Ben tells her she needs to stay alive and hopeful, if only to protect their children. In the background, the computer hums to life as Grace attempts to contact Ben. Aaron tells Miles about the special guns the Tower people are using – weapons that use electromagnetic power instead of bullets.
Aaron’s notebook on The Tower has a map that shows an armory with the weapons is nearby. Miles breaks off from the group and gets there, but it has been emptied. Outside, Tom Neville is talking to Reilly. Tom tries to convince him that the only thing wrong with the Monroe Republic is Monroe himself. Jason chimes in and tells Reilly that the best person to lead the republic is Tom. Reilly seems mostly convinced, but he isn’t ready to be part of a revolution; at least not yet. Inside, with Nora’s help, Miles manages to overpower one of the Tower people and get their special weapon. Rachel and Monroe are able to see what is going on via some TV monitors. Miles says that if Rachel helps him get out of the bunker, he will make sure that Charlie does not get hurt.
Nearby, one of the Tower people gets the drop on Charlie and is about to shoot her when Monroe blows the guy away. Rachel walks up as well. Looks like Monroe is on their team now too. Monroe goes off, leaving Rachel, Aaron, and Charlie alone. They are soon cornered by some of the Tower people. Monroe finds Miles and Nora. He has an electromagnet weapon aimed at Miles and Miles has one aimed at him. Rachel, Aaron, and Charlie are taken away by the Tower people. Grace is with the Tower folks and greets the group warmly. She goes up to Aaron and tells him he is well known to them. Rachel sees a man named Dan that she knew many years ago. He and his people were in charge of protecting the Tower when it was first turned on 15 years ago.
He tells Rachel that he and his children and his children’s children will protect the Tower for all eternity. He says they can’t let anyone get to Level 12 because it’s too powerful. Outside, Reilly comes to visit Tom and Jason Neville. Reilly unlocks Tom and Jason’s handcuffs. He hands Tom a gun and says that if they take out Franklin, the rest of the troops will fall in line and follow Tom. Back on level 11, Dan wants to burn the Tower notebook that will tell them how to turn the power back on. Aaron pleads with him, talking about all the good they can do and how they can restore society. Dan burns it anyway.
Grace turns to Rachel and asks her to tell everyone what will happen if the switch is flipped. Rachel says the lights will come on, but Graces adds that something else could also happen. Rachel says the odds of it happening are one in a million. Grace says that if she turns the power back on, maybe she turns just the power back on or maybe she sets the entire world on fire. The episode ends at this point.