As a result of Ben moving the island, the survivors left on the island begin skipping through time. Meanwhile, three years later in Los Angeles, Ben starts convincing the Oceanic 6 to return to the island.
Desmond returns to Oxford to fulfill Faraday's request to find his mother. Back on the island, the survivors discover that they've run into The Others 50 years in the past, but Richard Alpert is the same age.
John Locke, now alive again and back on the island after the second plane crash, flashes back to his return to civilization, where he is brought in by Charles Widmore and asked to convince the Oceanic 6 to return to the island.
Jack, Kate and Hurley wind up on the island in 1977, where they meet up with Sawyer and also join the Dharma Initiative. Meanwhile, Sun is stuck on the island in the present with Ben and the other passengers after the plane crash.
Jack refuses to help save young Ben after Sayid shoots him, so Sawyer and Kate turn to Richard Alpert for help. Meanwhile, what Sawyer said to Kate on the chopper is revealed, as well as what Kate did with Aaron before the flight.
Ben and Locke return to the island, where Ben says he is going to summon the Smoke "monster" and atone for his daughter's death. In addition, the falling-out on the island between Ben and Charles Widmore is revealed.
Miles is chosen by Horace to transport a dead body across the island. During the trip, Miles reveals to Hurley that Dr. Pierre Chang (a.k.a. Dr. Marvin Candle) is his father, whom he resents for leaving him and his mother.
Jack attempts to follow through with Daniel Faraday's plan to detonate the hydrogen bomb after Faraday is killed, Locke instructs Alpert to take him to Jacob, and Sawyer is interrogated about an incriminating surveillance video.
Jack and Sayid's plan faces resistance from Sawyer, Juliet, and Kate. Ben and The Others/Hostiles reach Jacob at the Foot of the Statue, and are soon met by the 316 survivors, who reveal the contents of their mysterious package.
Jack and Sawyer fight against each other about the fate of the island and the passengers of the Oceanic Flight 815 but Juliet ends the discussion, changing her mind. In the Swan station, Radzinsky is informed by Phil that a group is heading to the spot with a bomb. There is a shooting between Jack's group and Radzinsky's group with tragic consequences. Meanwhile, Locke, Ben, Sun, Richard and The Others head to the temple to meet Jacob. Locke and Ben enter in the temple and Ben stabs Jacob to death. Ilana reaches Richard and The Others and shows the content of the box ...