The episode begins with a family at home. The father bursts through the front door in panic and tells his wife that "it's happening" and she needs to start filling the bathtubs and sinks with water. Two Marines are shown driving back to base after a night out. The driver, Miles, gets a call from Ben telling him that "It's all going to turn off and never turn on again". Their connection suddenly dies and all of the cars on the highway stop running. Just before his computer goes black Ben downloads his hard drive onto a necklace-shaped device.
Planes are then seen falling from the sky and a shot from space shows the entire planet, go dark, as a result of a sudden and unexplained power failure. 15 years after the blackout, a man is heard teaching some kids that after the blackout nothing worked. Eventually militias rose up, as a result of the total disarray. People who stayed in the cites died he informs the kids, while the smarter ones moved to more rural areas, in order save themselves and survive. Nobody as it turns out, seems to know what exactly happened, that led to the whole power outage triggering off. Ben is living in a farm-like community with a teacher, named Aaron. Ben's children Charlie and Danny, now young adults, are also still shown living with him.
Danny as it turns out is an asthmatic and it is shown that he is being treated by Maggie, who is a doctor of some kind and is romantically involved with Ben, from the look of things. Charlie is battling Ben for her independence and it is then learned that Ben's wife was killed. On the other hand Tom, who appears to be a militia leader of some kind, rides into town on a horse with a bunch of men, his intentions apparently do not seem noble. Everybody seems highly nervous and Ben hands Aaron his hard drive and tells him to keep it safe. Tom wants Ben to come with him, and makes it amply clear that if he doesn't his children will be tortured. Ben is ready to go along as a result, but Danny appears with a gun, in order to prevent the whole thing from happening.
This leads to a standoff and eventually a shootout, between the two parties. Ben is mortally wounded in the whole process and Danny is captured in the bargain. Before he dies Ben tells Maggie to take care of the kids and advises Charlie to go to Chicago and look for his brother Miles. He should be able to help them find Danny, he reveals to them. Charlie prepares for the trip to Chicago. To her chagrin Maggie is also making the trip. Aaron makes it clear that he wants to join them as well. During a rest in the trip back to headquarters, Tom tells Danny he had no choice but to take him. He says that when General Monroe finds out he'll be in big trouble, for this decision of his. During the second morning of the trip to Chicago, Charlie runs into a young man named Nate.
Charlie, Maggie and Aaron find an abandoned plane. Aaron tells them he used to own an airplane at one point in time, he then elaborates that, he had been an executive at Google before the blackout. That night Danny manages to free himself from his handcuffs, knocking a guard out in the process, he then makes good his escape. Some men surprise the trio headed to Chicago while they sleep. Maggie manages to poison several of them with a bottle of booze she gives them and Nate shows up to finish off one with his bow and arrow, as a part of the whole process. Nate joins the trio on their trip. He tells them he's also headed to Chicago, hoping to catch on with a fishing crew. Maggie takes Charlie aside and says they can't trust anyone, given the current situation.
Charlie on his part doesn't seem concerned. Danny on the other hand is on the move, now that he has escaped, and clearly needs a place to sleep. The trio and Nate reach Chicago. They find the hotel Ben told Charlie about, and Maggie asks the bartender if he knows Miles Matheson. The water plays dumb in the beginning, but gives up his true identity when Charlie tells him she's Ben's daughter and his brother is dead. Turns out, the waiter is Miles Matheson. Danny wakes up with a woman pointing a gun at his face, much to his shock and horror. Her name is Grace she reveals and she tells him he had an asthma attack. Her son had asthma and she was able to save him with an inhaler. When he tells her he was running from Monroe's men she seems interested in helping him.
Miles tells Charlie that Ben must think he knows how to get the power going. The worry is that if Monroe figures it out first he'd be able to conquer the planet, with the help of the knowledge that he gains. Miles on his part has no interest in leaving, saying that Danny is bait and it won't work out well for either. Miles exposes Nate for being militia and he quickly departs. Miles realizes that Nate was sent to follow Charlie and hope she flushed him out. The plan clearly worked perfectly, as it turns out. He tells them they should leave, but he's planning to do no such thing, and instead is planning to just stay and wait for Monroe's men. Tom drops by Grace's home looking for Danny. She lies, saying she hasn't seen anyone in weeks. Tom has seen the tracks and Grace eventually lets him in.
Tom's men grab Danny upstairs, much to his dismay. Nate and some men return to Miles's hotel. Nate tells one of the men "Monroe wants him alive". Miles says he's not going back and a huge fight ensues, during the whole process. Miles dispatches man after man and is eventually assisted by Charlie when he gets surrounded. Charlie gets corned by one of the men and is surprisingly helped by Nate who quickly runs off. Miles finishes off the late of the militia. That night Miles says he'll come with them, given the recent turn of events. Miles later flashes back to the night of the blackout, and when it all started. The scene then flashes back and it is shown that, the other marine he was with that night was named Sebastian Monroe. Cut to Tom arriving at headquarters.
It is then shown that, Sebastian is now General Monroe, the head of the militia, and the person orchestrating all the violence. Grace on the other hand goes to a locked attic. She has a device similar to the one Ben gave Aaron. When she turns it on a bunch of machines come to life and a computer screen activates. She writes to somebody that the militia was there. The person writes back to ask if they found "it"? Grace writes no and the person in reply writes back "So ... what now?" The episode ends at this point.