Reunited with the survivors of the space-station Ark that fell to Earth, Clarke Griffin and her band of juvenile delinquents have faced death at every turn: from a world transformed by radiation to the fierce Grounders who somehow managed to survive it, and the double-dealing Mountain Men from the fortified Mount Weather, whose civilized environment masked a horrible secret. Though Clarke was alternately challenged, supported and betrayed by her own people and alliances with the Grounders, they could always find common ground in survival. United with the Grounder tribes, Clarke and her friends faced off against the lethal forces of Mount Weather to rescue the remaining "Sky People" from the Ark who were being held captive in Mount Weather. But victory came with a terrible price. The challenges continue in season three as they not only determine what kind of lives they will build, but what it will ultimately cost them.