The Arkadians (plus Emori and Niylah) are herded into the main room by angry clan members, where they'll wait to find out who are the 100 who will survive in the bunker.
Abby calls Raven and tells her that they're coming to get her. Raven tells Abby that they'll repeat the procedure on her to heal her brain. Kane overhears and wonders what she means about Abby being sick. Jaha, Clarke, and Bellamy join them to discuss what to do. After "essential personnel" and kids under 16, they have only 80 slots remaining.
Jaha argues that they should band together and fight for everyone of their people to survive. Kane refuses, saying they'll all die if they do that and says that their best bet is to hold a lottery. Clarke and Bellamy volunteer to go retrieve Raven. Murphy and Emori volunteer to go with them, in exchange for better chances at being able to stay in the bunker. Bellamy asks Murphy what he's up to, and Murphy accuses Bellamy of having screwed them over by opening the door. He tells him that he and Emori plan to go to the bunker on Becca's island, though Bellamy points out that the bunker isn't stocked long enough for them to survive there.
In the bunker, Kane announces the lottery plan and the situation to everyone. The people argue that they deserve more spots since they'll be running the bunker and try to throw Niylah out. Octavia intervenes and says Niylah is with her and safe. She tells the assembled Sky People that they are no different than the other clans and if they don't choose their people by midnight, they'll all die.
While driving to the island, Bellamy and Clarke have heart to heart about her choices. Suddenly, they swerve the truck to avoid hitting someone who jumped out in the road, but hit him anyway. They are attacked by a group of grounders who want their suits but are saved at the last second by Echo, who rides up on a radiation ravaged horse with bow and arrow. In exchange for saving their lives, she hopes they'll let her live on the island bunker. Unfortunately, they need another ride because the car is wrecked.
Back in the bunker, one at a a time, everyone writes their name (or the name of a family member, as Nate Miller's dad does) and puts it into the lottery. Abby tells Kane that she will be on the other side of the door when the radiation hits because of the things she's done. She insists that he pull 81 names.
A man named Jeff asks Jaha to watch over his son Ethan if his name isn't called. Jaha gets upset and suggests that they fight to live by getting leverage. He tells Jeff to get the grounders to open the door and he'll do the rest.
Bellamy contacts Monty by radio and asks him and Harper to swing by to come get them, since they have another rover. Monty and Harper agree to save their friends instantly. The group gives Echo one of the other radiation suits, but Emori is exposed when her suit is broken. Murphy tries to take the extra suit from Echo, not willing to let Emori die. Clarke gives her own suit to Emori, wanting to test to see if the nightblood works to resist radiation.
When Monty and Harper arrive, they give Clarke the extra suit but she starts to show effects of radiation poisoning, seeming to indicate that the nightblood might not work. Bellamy wants to get her back to the bunker rather than continuing to get Raven, saying that if her resistance does work, they can have Abby replicate it in order to save everyone else. Clarke insists on continuing to get Raven, saying that there might be a way to save everyone.
In the bunker, Kane begins calling names. Miller is safe. He and Jackson hug. Miller refuses to go in without his dad, but his dad insists. Jackson takes over calling the names when Kane notices that Jaha is up to something and goes after him. Jeff starts up a riot, announcing that Jaha has a plan to help them all survive and telling him to follow their lead. Jeff destroys the lottery bowl.
Kane finds Jaha, who informs him of his plan -- to gas the grounders and threaten to destroy the crops unless they make room for all of Skaikru. Kane tries to talk him out of it, saying he found salvation when he saved everyone by finding the bunker. Kane successfully talks Jaha down, but their people are already in a frenzy wanting to fight and they wonder how to stop them.
Indra tells Octavia that they've found Skaikru's armory and that they can't wait any longer. Octavia's people arm themselves and they head in to kill Skaikru. Indra offers to take care of this for Octavia, but O says it is her responsibility. When they go into the room, they find everyone except Jaha and Kane (who are wearing gas masks) unconscious -- Jaha and Kane used the gas on their people. Kane, in tears, determines that they will use Clarke's list to determine who will live.
Kane goes over the unconscious people, determining who will stay and who will go. Those who go (including Jeff) are carried out by the grounders. Kane asks an unconscious Abby for forgiveness and declares that she stays in the bunker.
The rescue team makes it to Raven, who didn't think they were going to show up. Clarke informs Raven that they will be going to space rather than back to the bunker. Raven points out that they don't have enough fuel to get back down, and Harper points out that it's a problem they can solve in five years. They can make food and water with what was left behind up in what remains of the Ark. Using an oxygenator that they hope is functional in the island bunker, they can make oxygen up there. Raven agrees to get them up to space.