Set 97 years after a devastating nuclear war wiped out almost all life on Earth. The supposedly only known survivors are the residents of "The Ark", twelve space stations in Earth's orbit that had banded together after the war. After the Ark's life-support systems are found to be failing, the 100 juvenile prisoners are declared to be "expendable" and are then sent down to Earth to determine if it is indeed habitable again. They land on Earth and find that they are able to breathe. There they meet the "Grounders", people who have been living on the ground for the last 97 years forming their own new culture and traditions in twelve separate clans all under the leadership of one commander. There are also the "Mountain Men" who live in a closed-off military bunker unable to leave for fear of dying in the radiation, using the grounders to supplement their blood supply. The 100 - Active Community - Lore - Great Plot - Troll Proof - Important ranks open!