Octavia is ready to prepare for an all-out war against Diyoza which Clarke opposes. Despite perfecting the algae, Monty's request to end the war and forget about the valley is ignored. Monty, sick of the unending violence, resolves to not go with his friends to the valley. Due to Octavia's unwillingness to listen to reason, Clarke and Bellamy decide to sabotage Wonkru's plan to attack the valley. Clarke and Bellamy enlist the help of Indra to sabotage Octavia's plan. They use the worms to kill Cooper, and attempt to make her death look like an accident. At the camp, Diyoza reveals to Kane that she is pregnant while the two discuss their plans for a better world. Raven finds out about Abby's addiction to pills, and feels betrayed when Abby tricks her into creating a device that can cure the lung disease of the Eligius prisoners. Later, Octavia finds Cooper's body, and immediately deduces Cooper was murdered and she reveals to Indra that she had planned to use the worm's eggs on the camp instead of the worms. Octavia arrests Clarke for treason and plans to have her executed. Bellamy and Octavia have dinner where Bellamy uses Monty's algae to poison her food.