Season synopsis
Contains spoilers for this season and earlier seasons.
Jack, Kate and Sawyer are prisoners of the Others: Sawyer is caged, Kate is put to work and Jack is interrogated by Juliet. Their leader, Ben Linus, offers Jack a way home in return for surgery to remove a spinal tumor. Jack bargains for Kate and Sawyer's release; Alex helps them escape while he stays behind. Locke, Eko and Desmond survive the Swan's destruction, but the smoke monster kills Eko; Desmond's visions begin warning him of events before they happen.
The survivors learn more about the Others' settlement and their interest in island pregnancies. Juliet returns to the beach under Jack's protection, and she tells Sun that her pregnancy could be dangerous. Locke leaves camp to confront Ben and is drawn into a reckoning with his father, Anthony Cooper; Sawyer kills Cooper after discovering he was the con man who ruined Sawyer's family. Meanwhile, Desmond repeatedly acts on visions that point toward Charlie's death, and the group finds Naomi, a parachutist whose arrival suggests rescue may be near.
The survivors prepare to use Naomi's radio to contact a freighter, while Sayid, Jin and Bernard stay behind to fight at the beach. Their dynamite ambush partly fails; Hurley drives a Dharma van onto the beach, and Sawyer and Juliet return, helping the captives turn the fight around. Charlie reaches the underwater Looking Glass station and disables its signal jammer, then learns from Penny that Naomi's boat is not hers. He locks himself in the flooded room so Desmond can escape and writes a warning on his hand before drowning. Jack leads the others to the radio tower; the closing scenes reveal that his apparent flashbacks are a future after leaving the island, and he insists to Kate that they must return.