Joe is sleeping when Norrie, wearing a gas mask, comes in and wakes him up. She insists that he come with her to the dome so they can figure out how they're connected to the dome. Norrie wants to talk to it and convince it to go away, and he asks her to step outside so he can put his pants on.
Julia wakes up in bed with Barbie, who is looking at her. When he starts to get up, Julia asks him to stay and Barbie starts to kiss her. There's a knock on the door but Julia says that they'll go away. The knocking persists and Julia finally goes down and answers it. It's a neighbor, Harriet, who asks Julia if she has any yogurt because it's the only thing she can keep down while she's pregnant. Harriet says that she's six weeks due and worried about her husband, Greg. Barbie comes down as Julia tells Harriet to come in and get some. When Julia wonders if Barbie is running away, he says that the town still needs his help.
Big Jim drags Junior out of Angie's room when he finds his son going to see her. He throws him out of the house as Junior insists that the dome is making Angie sick, and tells him that he'll make him sorry if he ever goes near Angie again. Junior begs his father to let him stay, but Big Jim closes the door behind him. Angie has heard the entire thing and warns Big Jim that Junior is crazy, and Big Jim says that Junior won't be a problem now. When he suggests that she stay there, Angie insists that she's not going to stay there because of his fear, and she's going home to Joe after she says goodbye to Rose. Big Jim explains that Linda left Rose's body in her diner. He gives Angie the keys and explains that he owns the place. He kept loaning Rose money to keep it open and finally just bought it. Angie realizes that Rose was his friend as well and Big Jim asks her to say goodbye for both of them.
Harriet leaves with the yogurt and sees Greg on the other side of the dome. He calls to her and Harriet runs over. As she tries to touch his hand through the dome, she gets a shock and the vision of Greg disappears. Harriet calls for Julia, who runs out as Harriet's water breaks, and the pregnant woman insists that the dome did something to her baby.
Junior goes to the police station and Linda tells him that he's the only deputy who showed up. Barbie comes in and Linda says that they need to find the Dundees. She tells Junior to go on patrol but he insist that he can talk down the Dundees because he knows them. Barbie agrees and Junior and Linda load up.
Julia gets Harriet into her house and the woman explains what happened, and the editor takes her to the hospital.
Angie goes to the diner and finds Rose's body in the back. As she goes to it, Ben comes in and tells her that Joe is with his new girlfriend. He sees Rose's body and Angie asks him to help her with something.
Ollie is handing out water and assuring the townspeople that there's plenty when Big Jim arrives. Big Jim points out that he's the one paying with propane, and says that he's there to bury the hatchet. The councilman wants to get the town back on track, but Ollie isn't buying it. He asks Big Jim if he's sure that he still has the propane. When Big Jim wonders what he means, Ollie just grins and walks away.
Joe leans up against the dome and Norrie kisses him, but nothing happens. He suggests that they're going about it wrong and they should try to find the center. Norrie agrees and kisses him before they leave.
Big Jim drives to the propane storage warehouse and discovers that Ollie's friend Boomer is there. Boomer is armed and warns him off, and Big Jim realizes that they've broken in. When he tries to shove past Boomer, Boomer beats him to the ground and the councilman drives off.
As Barbie patrols the town, he spots the Dundees looting a gas station. They run off and Barbie goes after them.
As they drive around, Junior asks Linda what they'll do with the Dundees if they capture them. She says that they'll lock them up and deal with them later, and says that they were going to rape Angie. Furious, Junior promises that they won't get away.
As Julia drives Harriet to the clinic, they come to a barricade. The Dundees force them over at gunpoint and start siphoning gas out of the SUV. Barbie comes up behind them and knocks down one of them, but Harriet screams in pain and Barbie goes to her. As the Dundees run off, Barbie calls it in to Linda. He tells Julia that the clinic is closed and she suggests that they go to see Alice because she's a doctor.
As they drive, Junior suggests that the Dundees are hiding at a salvage yard where the kids used to play. When he says that he plans to kick their butts, Linda insists that they're going to arrest them and that they're not vigilantes.
As Joe homes in on the center of the dome using the map that he and Ben created, Norrie worries about Alice, who is running out of insulin. Joe admits that it's awesome that they're the focus of what happened because it's the first time such a thing has happened, and he wouldn't have met Norrie if it hadn't happened. Truman starts barking and then runs off, but Joe insists that they have to continue.
Angie and Ben bury Rose, and Angie admits that she didn't appreciate her because she was busy wanting to be someone else. She tells Ben to help her clean the place up just as Big Jim comes in. Angie notices that he's injured but Big Jim just says that there's people making trouble for themselves. He pours himself a drink just as Ben comes back in, and Big Jim makes sure that Angie hasn't said anything to Ben about Junior. The councilman tells Angie to clean the blood up and walks out, and Angie nervously closes the door behind him.
Carolyn tends to Alice, who insists that she doesn't want to be treated like an invalid. Her wife invites her to dance and Alice accepts. As they dance, Carolyn apologizes for bringing her there but Alice reminds her that she agreed and that it's no one's fault. Julia and Barbie arrive with Harriet and explain what happened, and Alice tells her that she's going to have the first baby born inside the dome.
As they continue walking, Norrie notices that the hair is standing up on her arms. They find a mound and when Joe touches it, he gets a shock. The same thing happens to Norrie, and they scrap aside the leaves to reveal a metal hemisphere several feet across. Norrie pours some water on it, clearing away the dirt. Inside it is a small black egg-like object.
Harriet goes into labor and begs for her husband Greg, and Alice assures her that it happens every day. Julia tries to reassure her friend but Harriet insists that with everyone trapped, people will just continue acting worse and worse. Barbie points out that good things happened and they helped her, and tells her to focus. He takes her hand and Alice tells her to push.
Ollie comes to see Big Jim at his office, well aware of what happened. He tells Big Jim that he's got the well, the propane, and the crops, and tells Big Jim that he's going to toe the line from now on. Ollie leaves and Big Jim takes another drink.
Waylon and Clint Dundee hole up at the salvage yard. Clint is worried that Barbie is going to catch up to them, but Waylon figures that there are a lot of opportunities for them. Junior gets the drop on Clint and Linda comes up behind Waylon. She shoves Waylon up against the wall but he shoves her back and Clint jumps Junior and then runs off. Linda shoots Waylon, while Clint finally trips. When Junior catches up to him, Clint begs him to take him in. Junior guns him down and Linda hears the shot. She runs up and he tells her that he got him.
Joe tries to give the egg voice commands but nothing happens. It doesn't work and Norrie orders it to respond. Joe suggests that they touch it together. An image of Alice appears nearby, but disappears as soon as Norrie jerks her hands away from the miniature dome. Norrie runs off to find Alice while Joe covers the dome over with leaves and then goes after her.
Alice collapses and Barbie takes over.
That night, Boomer is taking out the propane tanks to his truck when he hears something moving. As he gets in the cab, Big Jim fires and hits the propane tanks, setting them on fire. Boomer's truck explodes while he's inside it, and Big Jim takes another swig of whiskey.
Carolyn tries to hold Alice back, but she insists on going over. She tells Harriet to stop pushing because the cord is wrapped around the baby's neck. Alice tells Barbie and Julia how to tie it off and cut it, and then tells Harriet to make one last push. Harriet delivers a baby girl and they swaddle her up and give her to her mother. Crying, Harriet thanks them all and Alice asks to hold it. After a moment, Harriet tells her that she's naming her child Alice. As they give the baby back, Alice collapses, saying that it's her heart.
Angie and Ben finish cleaning up the diner and she smiles. When Ben asks why, Angie says that it's the first time she's worked there without feeling pissed off. Junior comes in and tells Ben to go home, but he refuses. Undeterred, Junior tells Angie that he knows he can't make her love him. He apologizes and Angie tells him to leave now that he's said it. As he goes, Junior tells Angie that the Dundees will never bother her again.
As Carolyn tries to make Alice comfortable, Julia tells Barbie that it was amazing what he did. Norrie and Joe come in and Norrie goes upstairs to her mother. Carolyn tells her that Alice had a heart attack and they go to her. Alice looks up at her daughter and smiles.
Joe goes outside to wait, and Ben and Angie arrive. Brother and sister hug and Angie says that she's okay.
Norrie tells Alice that she saw her in the woods and figures that the dome tried to warn her. Alice explains that Harriet said the dome made her see her husband, and now there's a new Alice. She figures that it all matters and that the dome brought Norrie there because it wants Alice to go. Alice is grateful that she got to see her daughter one last time and tells them to take care of each other. Norrie insists that her mother isn't going anywhere, but Alice says that she is and tells her to be brave. After a moment, Alice dies and Norrie and Carolyn break into tears.
After a moment, Norrie runs outside and Joe goes after her. She falls to the ground at the edge of the dome and touches it, begging it to bring Alice back.
Carolyn sits down on the bed and strokes Alice's hair.
Barbie and Julia lie on the couch and hold each other.
Carolyn kisses Alice and then holds her tight.
The townspeople find the wreckage of Boomer's truck. Big Jim arrives and looks at Andrea, shaking his head.
Norrie yells at the dome, asking what it wants. In the forest, the black egg glows.