Clarke is recaptured by Anya, and held in a temporary camp when the camp is visited by a grounder named Tristan. Tristan takes command of the grounder group, suggesting a military structure. Clarke is ordered executed, to be carried out by a grounder who turns out to be Lincoln. They ride a horse to a clearing where Finn greets them. Lincoln leads the two into a mine network that has a new enemy the grounders are also afraid of - reapers. The reapers are strong, vicious cannibals. Lincoln leads them away, and Clarke and Finn make their way through. Finn is forced to kill a reaper in self-defense. They make it back to the camp where Murphy has been involved in a hostage situation. Having been discovered murdering Miles by Jasper, Murphy takes Jasper hostage. Bellamy trades himself for Jasper, while Raven and Jasper attempt to open the dropship door. As Murphy lynches Bellamy, the door opens and Murphy retreats to the upper level. He blows a hole in the ship with gunpowder and escapes with a radio. Clarke convinces the group to flee the camp for the ocean. On the ark, the residents come to terms with the imminent failure of the ark. As Jaha watches a video of his son, he realizes a solution that may save everyone - use the ark itself as a dropship to earth.