Season synopsis
Contains spoilers for this season and earlier seasons.
After Oceanic Flight 815 breaks apart over the South Pacific, doctor Jack Shephard helps the scattered survivors organize on a remote island. The beach camp faces scarce food and water, a wounded marshal, a mysterious creature in the jungle and a radio signal repeating a French woman's distress call. As the group splits between the beach and nearby caves, flashbacks reveal how Jack, Kate, Locke, Sawyer, Sayid, the Kwons and others arrived on the same flight carrying secrets and unfinished relationships.
The island's threats become more personal when Ethan, an outsider who had passed himself off as a survivor, kidnaps pregnant Claire and Charlie. Claire returns with no memory of her captivity, and Charlie shoots Ethan dead after he threatens the camp. Charlie struggles with heroin withdrawal and reconnects with Claire after she gives birth to Aaron; Locke and Boone keep trying to open a metal hatch, but Boone dies after a small plane crashes while he investigates it. Michael, Sawyer and Jin finish a raft, while tensions among the survivors deepen around the guns, the numbers and whether Locke should reveal the hatch.
Danielle Rousseau warns that the Others are coming, and the survivors split their efforts: Jack, Kate, Locke and Hurley carry dynamite from the Black Rock to open the hatch while Michael, Walt, Sawyer and Jin launch the raft. Rousseau briefly takes Aaron after misunderstanding the Others' warning that they were coming for a boy, then gives him back. At sea, strangers seize Walt, shoot Sawyer and destroy the raft. The hatch is blown open, leaving Jack and Locke staring into its dark shaft as the survivors face a new mystery below ground.