After poisoning his sister
about it but lies to Madi
and everyone else that Octavia
is just sick. They agree to leave Clarke tied up while they initiate their plans for peace. The plan is for Indra to take over as the leader of Wonkru
and convince them that they shouldn't go to war. Indra gathers all Wonkru to tell them about Octavia's illness. She also announces that she's taking over as the leader in Octavia's absence since she was Octavia's teacher. However, when she mentions that they won't follow Octavia's wish to go to war, she faces immediate opposition from Octavia's loyalists led by Miller
Since no one can listen to them, Indra and Bellamy devise a plan to have Madi become the commander. They would then use Madi to do according to their ideologies and the grounders would listen to Madi because she's a Nightblood. Indra asks her daughter, Gaia, the Flamekeeper to perform the ascension ceremony for Madi. Gaia is reluctant because she made a promise to both Madi and Clarke. Gaia agrees to do it only if Madi accepts the flame. Madi doesn't want to take the flame because Clarke wouldn't want that. But Bellamy convinces her to take it, by lying to her that it would be the only way to save Clarke. When Bellamy goes to Clarke and tells her about the plan, Clarke refuses to accept it because Madi is just a child and they would be putting her in danger. So, Bellamy decides to keep Clarke chained until the ceremony is over.
When Indra goes to check in on Octavia's progress, she's shocked when Jackson tells her that Octavia is waking up. Octavia weakly calls Indra and mentions that Bellamy poisoned her. At that point, Indra attacks Jackson to make sure he doesn't tell anyone about Octavia being poisoned. She locks the door and says that no one is allowed to get out. Octavia calls out Indra for her treason and for being a coward. Indra justifies herself by saying that she wants to help Octavia with the burden because she feels responsible for what Octavia has become.
On hearing about Madi's ascension ceremony, Niylah goes to Clarke to ask why she would allow Madi to take the flame. Clarke then tells her that she is against it too. She also reveals that Bellamy and Indra are the ones who poisoned Octavia so that they can make Madi the commander. She convinces Niylah to release her from the chains because they both want the same thing - to stop Madi's ascension. Niylah agrees and steals a key from one of Indra's people to get access to the room Octavia is locked. Since Madi's ascension has begun, Clarke realizes that the only way to keep Madi safe is to kill Octavia. She goes into where Octavia and Indra are. She points a gun at Octavia. After a little argument, Octavia convinces Clarke that they're on the same side. They both don't want Madi to become the commander. So, Clarke and Octavia make a deal - Clarke would help Octavia stop the ceremony and Octavia would help Clarke and Madi escape to the valley.
By the time they get to Madi's ascension ceremony, Clarke and Octavia find that Madi has already taken the flame and is unconscious waiting for the flame to take over. Octavia orders her guards to arrest Bellamy, Gaia and Indra for treason. She then asks one of her guards to take Clarke and Madi to the rover. After getting to the rover, the guard tries to shoot them in Octavia's name. But then Madi wakes up and asks him to drop the gun. She recites the lineage, implying that the ceremony worked and she's now a rightful commander. The guard kneels down and calls Madi "Heda!" But then, Clarke shoots the guard and forces Madi into the vehicle against her will.
Following the incident, Octavia gathers Wonkru around the ring ready to have Bellamy, Indra and Gaia fight to the death. She lies to them that Madi's flame didn't work because she didn't recite the lineage. She tells them that Madi ran away like a coward instead of staying to fight for Wonkru. She declares that Madi is not Wonkru, she's an enemy of Wonkru. And they will deal with her later. For now, they have a war to win. Octavia then sits down in her throne, watching her own brother as a captive. She sheds tears.
Meanwhile at the valley, Murphy and Emori are reunited with Raven and Echo. They start brainstorming on how to escape. Echo brings up her plan to kill Shaw so that Raven can become the pilot and use the ship against the prisoners. But Raven tells them that Shaw could be useful to them as a spy. She comes up with an idea to divide the prisoners through infighting. While the prisoners are fighting, Raven and Emori would then quickly disable the collars from their people and escape. Raven asks Shaw to come with them but when Shaw refuses, Raven threatens him. So, Shaw agrees to let them take off his collar.
Murphy figures out that dividing the prisoners should be easy because there's already rivalry between McCreary and Diyoza's people. McCreary is mad that Diyoza refused to trade Raven for his life. And Diyoza has been asking Abby to hide the cure from McCreary and his people so that they can all die out. So, Murphy tells McCreary about the cure to make him angry at Diyoza; and Echo tells Diyoza to prepare for McCreary. This leads to a showdown between McCreary and Diyoza's people. Diyoza tries to avoid a fight by coming clean about the cure and telling them her plans for the valley. This calms both sides down, to Murphy's disappointment.
Out of options, Murphy decides to incite a fight by throwing a stone at the crowd. This instantly causes both sides to break into a fight. With Murphy's job done, he goes back to the church where Raven and Echo are quickly turning off the collars from their people. Just before they escape, Kane comes in and tells them that they have to save Diyoza. He tells them about the peace plan he initiated between Diyoza and Clarke. While Murphy and Raven feel guilty for jeopardizing the peace plan, Echo confidently believes that there is no way Octavia would surrender. Murphy agrees to go with Kane to save Abby and Diyoza while Raven, Emori, Echo and Shaw escape into the woods. Murphy and Kane go to the medical room where McCreary and Diyoza start fighting for Abby. McCreary's men manage to capture Abby. Diyoza beats McCreary down as she reveals that she's pregnant with his baby. One of McCreary's men gets up and is ready to shoot Diyoza just before Kane arrives and shoots him down.
Diyoza flees into the woods with Kane, Murphy, and the others. Afterwards, McCreary wakes up and declares that he's taking over the leadership. He orders his people to hunt all the traitors especially Shaw, Raven and her friends. He also makes it clear that he will not honor Diyoza's peace treaty with Clarke.