Storyline : 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. The upcoming episode is titled ‘A Sort of Homecoming.’ The CW has released the official synopsis, which gives us more insights into what the next part has in store for fans. It reads as follows: “Clarke and her friends reckon with all that has happened only to find an unexpected threat looming.”