The warriors prepare to fight in the conclave. Luna arrives and says she'll be fighting on behalf of her clan, of which she's the only remaining member. She wants to win so that humanity will die out, because she no longer believes anyone is worth saving. Clarke becomes very uneasy, assuming that Luna will definitely win because she's trained for the conclave. The rest of all the clans are sent away out of Polis except for two advisors for each conclave participant who get to remain behind.
Before the fight, Indra and Octavia have a heart to heart and Indra wishes Octavia luck. Bellamy and Kane give Octavia advice not to try to fight everyone, but to use her past as the girl under the floor to hide out and wait to take out the last person standing. Octavia agrees.
During the conclave, Luna massacres many participants, as does Roan. Ilian fights for his own clan and offers to team up with Octavia, who refuses. He saves her anyway during a fight but moments later he is suddenly shot through the throat with an arrow. Octavia mercy-kills him. Bellamy sneaks onto the battlefield to check on his sister, finding that Echo is intervening by shooting people with a bow and arrow from up in a tower. Bellamy begins choking her but is stopped by Roan, who banishes Echo for having cheated in the conclave and dishonored Azgeda.
After Echo leaves, Roan and Bellamy have a conversation about Octavia, as Octavia (unseen) listens in. Bellamy makes clear how much he loves his sister, and Octavia overhears and is happy.
During the conclave, Roan and Octavia face-off, but Roan offers her a temporary truce instead, pointing out that neither of them can take down Luna alone. He suggests they team up to take down Luna and then fight one another after. Octavia agrees.
Luna kills the fourth remaining fighter before facing off with Roan and Octavia. Black rain begins coming down, causing Octavia to need to run and hide. Luna manages to get the upper hand and stabs Roan, then drowns him. Luna then comes after Octavia, who uses her hiding skills to trick Luna and then kill her.
Octavia returns to the Polis tower as the last remaining fighter, but announces to all congregated that she won't allow only Skaikru to take the bunker -- she says she was fighting for everyone and that they're one clan. Everyone cheers for her. Unfortunately, while everyone was distracted, Jaha and Clarke seized the opportunity to disable the guards around the bunker and get Skaikru sealed into the bunker, claiming the bunker unfairly for their clan. Bellamy wakes up inside the bunker, having been kidnapped by Clarke after his confrontation with Roan, and is confused about what's going on. Jaha informs him that this plan was Clarke's idea.
Everyone in Polis realizes what Skaikru did and their betrayal when they find the bunker door sealed. Octavia and Kane, along with the rest of all the other clans, remain outside the bunker doors.