After a close call last week, Bellamy is back in action and his first order of business is freeing the Grounders from their Harvest Chamber cages. He is keeping his promise to Echo and she is on board to ready the Grounder army inside the mountain.
And an army will certainly come in handy. While the prisoners are being freed, Cage is announcing to all of Mount Weather that there is a cure for their radiation sensitivity and turning over the hidden 44 prisoners is the first step to life on the ground.
Cage knows that there is an army outside, but he isn't going to give them a fight unless he has to.
Jasper and Maya are hiding in the home of a couple who is opposed to the blood treatments. When security comes for them, Jasper and Maya turn themselves in to save their life, but security kills the couple anyway.
Outside Mount Weather, the Grounder army awaits orders and Clarke goes over the plan.
There are 4 teams. The first is with Raven and Wick at the dam. They are there to kill power at the Mountain which will disengage the electromagnetic locking system on the door. Once they blow the power, they will have one minute before the backup generator kicks in. Blowing the backup generator is not an option because it will leave the civilians inside the Mountain exposed to radiation for too long.
The second team is with Indra and Octavia at the mines. They will disable the reapers using the tone generators and tie them up, making the tunnels safe for the prisoners to escape.
The third team is made up of the Grounder army inside Mount Weather.
The fourth team is outside the doors, with Clarke and Lexa at the helm. Their main job is to keep eyes off the other teams and also be there to take down the door once Raven and Wick blow the power.
At the mountain, Maya's dad, Vincent, helps distract the guards so Miller can attack and free Jasper and Maya.
Bellamy, Jasper and Maya take off for level 3 to find Monty, while the rest hit the Harvest Chamber to meet up with the Grounder army there.
Octavia and Indra are in the mines. They are able to disable the Reapers, and Indra becomes slightly emotional at the sight of one in particular.
Raven and Wick are at the dam setting bombs on each turbine. When a Mountain Man comes at them, Wick takes him down. One of the bombs is broken in the process, which puts the plan in trouble.
Cage, meanwhile, realizes that he is failing as President. He consults his dad for advice.
Outside the mountain, Clarke is worried. Lexa asks her about future. Clarke doesn't know what she wants, except that she needs her people to be free before she can think about it. Lexa wants her to come to the capitol with her.
Raven has an idea to blow the last turbine in lieu of a bomb. While dangerous, it should achieve the necessary result. Wick and Raven are caught in the process. They are close to the turbine, but the Mountain Men are closer. Wick tells Raven to keep backing up before the turbine blows.
With the power down, Clarke and Lexa hit the button to blow the door, but the detonator isn't working. The Mountain Men must have jammed the signal. Shots are fired and they have to take cover.
Sgt. Miller uses the Grounder shield wall to get him to the door, but the wall is gunned down in the process. Lincoln shoots a flame arrow at the door and it works. Lexa leaves to take out the shooters on the ridge.
An announcement made at the mountain tells all residents to go to level 5, which will be the only radiation-free level once the doors are opened. Since Maya can't go to level five without being killed, she is not in a good position.
They find Monty, who tells them that he overheard Mountain Men talking and they know about the Grounders in the Harvest Chamber.
At the doors, Lexa returns with a Mountain Man at her side. She orders the Grounder army to stand down. They are not surrendering, but instead have made a deal. Lexa has negotiated the freedom of her people, but this deal did not include the captive Arkers, She sounds the retreat and leaves Clarke helpless.
Lincoln puts up a fight to help the Sky People but is overpowered.
Indra hears the retreat call and orders everyone to leave the mines. Octavia doesn't trust Lexa and won't leave with her brother. Indra renounces her as second and leaves.
Meanwhile, Bellamy and the rest reach the Harvest Chamber to find all of the Grounders gone and Vincent dead.
Raven and Wick survived the turbine blast, but are caught by Mountain Men.
Clarke stands at the massive doors to the Mountain, looking up. As Clarke says, "It can't be over."