Season synopsis
Contains spoilers for this season and earlier seasons.
Season six follows two parallel threads: on the island, the survivors return to 2007 after the flash; in the flash-sideways, Oceanic 815 lands safely in Los Angeles. The man posing as Locke is revealed as the smoke monster and recruits people who want to leave, while Jacob's remaining followers try to protect the island. Jack, Hurley, Kate, Sawyer and the others are pulled between the Temple, beach, Widmore's submarine and the Man in Black's camp as they learn that several of them are candidates to replace Jacob.
The rivalry becomes a direct fight over who can leave and what the island protects. Sayid joins the Man in Black and helps destroy the Temple's defenses, then later sacrifices himself to carry a bomb away from the others. At the submarine, an explosion traps Sun and Jin together; Jin stays with the trapped Sun as the vessel floods. Jack, Kate, Sawyer and Hurley escape, and Jack accepts the role of island protector. He also understands that the apparent Locke is the enemy Jacob had kept from leaving.
Desmond is taken to the island's heart, where removing a stone plug extinguishes its light and makes the Man in Black mortal. Kate shoots him during the final fight, and Jack knocks him from a cliff. Jack sends Kate away, then appoints Hurley protector before restoring the light. Kate, Sawyer and Claire escape aboard the Ajira plane with Lapidus, Richard and Miles. Jack dies from his injuries after watching their plane depart. In the flash-sideways, Desmond helps the survivors remember their island lives, and Christian explains that this shared meeting place exists beyond ordinary time so they can reunite and move on. Their island experiences were real; the sideways story does not mean they all died in the crash.