The.100.S03E14.720p.English-

The series follows a group of Delinquents, who have been sent down to Earth to see if it is survivable or not. For the first time in nearly a century, humans have returned to planet Earth, but they realize they're not alone.
Set in 2149, 97 years after a nuclear apocalypse has devastated the surface of Earth, the only survivors were approximately 400 inhabitants of 12 national space stations that were in orbit at the time. Three generations have survived in space. The Ark has strict measures, including capital punishment for those over 18 and population control, as the leaders of the Ark take steps to ensure the survival of the human race. But now, resources are running out and the Ark is dying. For the first time in nearly a century, there is talk of returning to Earth.
100 juveniles convicted of various crimes are sent to Earth to see if it is survivable. Among them are 17-year-old Clarke Griffin, the daughter of the Ark's chief medical officer and of the Ark's chief engineer; Wells Jaha, the son of Chancellor Jaha; the daredevil Finn Collins; the illegal sister Octavia Blake; her stowaway brother Bellamy Blake; the lighthearted Jasper Jordan; and the resourceful Monty Green.
Technologically blind to what’s happening to the 100 on Earth, the Ark’s leaders Chancellor Jaha, second-in-command Marcus Kane, Councilwoman Abigail Griffin and the Council are faced with difficult decisions about life, death and the continued existence of the human race.
For the 100, Earth is an alien planet; however, they quickly discover that Earth is filled with new wonders and dangers of all sorts. Then, they discover that not all humanity was wiped out, and some survived the nuclear apocalypse: the Grounders, who live in 12 clans locked in a power struggle; the Reapers, another group of Grounders who have become cannibals; and the Mountain Men, who live in Mount Weather and locked themselves away before the apocalypse.
In the third season, Camp Jaha, now renamed Arkadia, comes under new management when Pike, a former teacher and mentor, is elected over Kane as Chancellor and begins a war with the Grounders. An artificial intelligence named A.L.I.E. was revealed to be responsible for the nuclear apocalypse that devastated Earth 97 years before the series, and she takes over the minds of nearly everyone in Arkadia and Polis – the capital city of the Grounders. In the third season finale, Clarke manages to destroy A.L.I.E. after it is revealed that the world is facing another nuclear disaster. This is due to nuclear reactors around the world that have fallen into disrepair and are irradiating Earth, once again threatening to make it uninhabitable.