100 years in the future, when the Earth has been abandoned due to radioactivity, the last surviving humans live on an ark orbiting the planet — but the ark won't last forever. So the repressive regime picks 100 expendable juvenile delinquents to send down to Earth to see if the planet is still habitable.
After arriving on a new planet, our heroes found a place where they hoped to try again. Clarke and Bellamy led a group down to this mysterious world to start anew, but not everything on Sanctum was as perfect as it seemed. Despite their determination to do better, threats both seen and unseen once again forced them to fight for their lives and the future of humanity.