When the hatch suddenly takes on a life of its own, Locke is trapped alone in the bunker and is forced to enlist the help of an unlikely ally: the captive Henry Gale to try to free him. Meanwhile, Jack faces off against Sawyer in a series of card games for supplies. Also, Ana Lucia, Sayid and Charlie find out the truth about Henry in the jungle.
When Sun comes to the realization that she might be pregnant, she struggles on whether to tell Jin about the situation. After no success from Jack or Sayid, Ana-Lucia is called in by Locke to interrogate the prisoner, Henry Gale, to get more information out of him about how he arrived on the island. Ana-Lucia, Sayid, and Charlie then set out into the jungle to try and confirm Henry’s story.
The harrowing first 48 days in the lives of the 23 tail section survivors are revealed, formally introducing Ana-Luca, Mr. Eko, Libby, Cindy, Bernard, and Goodwin detailing the first terrifying days and battling the dreaded “others”, leading to their numbers dwindling, their hikes though the jungle, and meeting with Jun, Michael and Sawyer.
A desperate and growingly insane Michael sets off into the jungle by himself determined to find Walt, but discovers that he is not alone. Meanwhile, Sawyer and Jin are ordered by their captors, the tail crash survivors, to take them to their camp. But they are delayed when Jin and the hulking Mr. Eko are forced to go into the jungle to look for Michael before the dreaded “others” find him first. Back at the beach camp, Sun frantically searches for her missing wedding ring which triggers flashbacks to Sun and Jin’s past showing how they met for the first time in early 1990s Seoul, when Jin was working as a doorman of a fancy hotel where Sun was staying at for a courtship engagement set up by her mother.