Sawyer's wound becomes life-threatening as he, Michael and Jin make their way through the interior of the island with the tail section survivors. Meanwhile, Shannon is once again haunted by visions of Walt.

Jack, Locke and Sawyer follow after a determined Michael after he heads into the jungle toward the dreaded "Others" in search of Walt. Meanwhile, Sun has a surprising reaction to Jin's desire to join the search party, and Hurley and Charlie commiserate over the age-old conundrum of "what women want."

Sun comes to the realization that she might be pregnant. She struggles on whether to tell Jin about the situation. Meanwhile, with no success from Jack or Sayid, Ana-Lucia is called in by Locke to interrogate the new prisoner Henry Gale to get more information out of him about the balloon that he and his wife supposedly landed on the island with.

After finding an exhausted Michael in the forest, Jack and Kate bring him back to the main camp. When he finally wakes up, Michael has some new details about "The Others." Also, a lovestruck Hurley plans a date for Libby.

Locke, Eko and Desmond are found scattered about the island after the implosion of the hatch. Locke receives a message from the Island asking him to fix the situation he caused.

Hurley returns to the beach camp to report the imprisonment of Kate, Jack and Sawyer by the Others.

Desmond has been fundamentally altered by the implosion, giving him a mysterious new power.

As Kate and Sawyer journey back to the main island with Karl, who is exhibiting effects of the brainwashing video, they argue over whether to go back and save Jack. On Hydra island, as Juliet's fate rests in his hands and a power struggle within the Others ensues, Jack recollects the time he spent in Phuket, Thailand and his relationship with Achara, a mysterious tattoo artist.

Kate and Juliet are stranded in the jungle after Kate learns that there is a traitor in the survivor's midst. Meanwhile, Sawyer's poor attitude and selfish ways towards the beach community may earn him a vote of banishment if he doesn't have a change of heart.

Ben unwillingly divulges information to Locke about the island, taking him on a journey to various locations including strange monuments and the mysterious Jacob. Back at the beach, Juliet's secret is revealed. Flashbacks will show us the origins of DHARMA and the history of the island, including 'the purge.'

Michael is tied up, when Juliet walks in. She tells him the boat is his, so that he can take Walt away after he will have saved Ben. She comments that Walt is special, that he's not an ordinary boy, and that's why she is worried about him. Juliet is glad that Michael is going to get Walt away from the Island and assures him that Ben will do what he wants. She then reveals the deal with Ben she has made herself, concerning her sister. Then she mentions Michael's list and wishes him good luck.

Juliet is outside Room 23 where there is some sort of commotion and an alarm sounding. Ben arrives and Juliet tells him that he (presumably Walt) has done something again and that everybody is too scared to go in there. Juliet suggests that they could bring him back to Michael, but Ben refuses. Ben tells her that Walt is special and that Jacob wanted him there, but Juliet says that he is dangerous. When Ben counters that he is only a child, Juliet brings him outside to show what he has done: a group of dead birds lay on the stairwell.

Kate needs to get information out of the hostages, but it may jeopardize her standing with Locke -- as well as with Sawyer. Meanwhile in the future Kate's Court hearings take place.

Sayid confronts Ben's spy on the freighter, and Ben urges daughter Alex to flee Locke's camp in order to survive an impending attack.

Locke finds out where Jacob's cabin is. Life on the freighter becomes dangerous.

Desmond looks for a woman who might be the key to helping Faraday stop the island's unpredictable movements through time; Locke finds out who has been attacking the survivors.

Sawyer perpetuates a lie with some of the other island survivors in order to protect themselves from mistakes of the past.

To atone for sins of the past, Ben must attempt to summon the smoke monster in order to be judged.

Jack and Kate find themselves at odds over the direction to take to save their fellow island survivors, Locke further solidifies his stance as leader of "The Others," and Sawyer and Juliet come under scrutiny from the Dharma Initiative.

On the island, the Man in Black attempts to recruit Sawyer in his attempt to leave the island, while an impromptu funeral is held for the real Locke. In the flash sideways, Locke is fired from his job and becomes a substitute teacher.

The Man in Black sends Sawyer on a reconnaissance mission to Hydra Island, where he discovers that Charles Widmore has returned to the island with a team of scientists. In the flash sideways, Sawyer is a lonely cop who is still searching for the original Sawyer.

After the remaining survivors are reunited, Sawyer and Jack hatch a plan to divert the Man in Black's attention and leave the island without him on Widmore's submarine, but disastrous consequences await them. In the flash sideways, Jack investigates the cause of Locke's paralysis and offers treatment.

Ben finally takes his revenge on Widmore after accepting the Man in Black's request for assistance. Jacob explains the purpose of the candidates, and Jack volunteers to take his place. The search for Desmond reveals that he has been rescued and the Man in Black plans to use him to destroy the island. In the flash sideways, each person ends up on their way to a concert.