The 100 have been sent to earth 97 years after a nuclear apocalypse to see if it's safe for the population to return. But they have quickly realised they're not alone and the Grounders don't like the newcomers coming to their territory.
Up on the Ark, Abby exposes Kane's plan to reduce the population, but soon she and Chancellor Jaha notice a signal and realise some of the 100 must still be alive.
Down on the ground, Clarke's romance with Finn is threatened by a new arrival in camp, and Octavia's knocked out after a fall and wakes to find a Grounder watching her...
The 100, E4, 9pm
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