Michael’s whereabouts during his 13 days in captivity in the “Others” camp are detailed while in the present, he tries to convince Jack to help him mount a search party for his son Walt still being held captive. Meanwhile, Locke struggles with a choice whether or not to abandon the hatch.
Mr. Eko enlists Locke to help find a secret location he believes houses answers to the island’s mysteries. Meanwhile, Jack, Sawyer, and Kate struggle to cope with the horrific situation in the hatch following the escape of “Other” Henry Gale, and of the shooting deaths of Ana-Lucia and Libby, unaware that it was Michael who is responsible.
Hurley begins to think the island is affecting him in a very strange way, so Libby attempts to offer him support. Hurley also recalls his past in a mental hospital with his friend Dave. Meanwhile, the prisoner calling himself Henry Gale offers new information about the Hatch, which severely shakes Locke’s sense of purpose.
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.
Survivors fear that “The Others” may have returned when Sun is injured during a failed kidnapping attempt. Meanwhile, Sawyer is an amused, but highly interested, bystander when tension escalates between Jack, Locke, Kate and Ana Lucia over control of the hatch computer, and the storage of the weapons.
Kate’s original crime that started her life on the run is revealed. Meanwhile, the survivors lay one of their own to rest, Kate sleeplessly watches over a feverish Sawyer, and Mr. Eko has a surprise for Locke regarding the hatch.
Disturbing memories from Hurley’s past cause him to struggle with a task he’s assigned inside the hatch to watch over the food storage locker. Meanwhile Sawyer, Michael and Jin discover the identities of their captors whom are what’s left of a group of two dozen Flight 815 survivors from the tail end of the plane led by the tough minded Ana-Lucia Cortez who insists they walk to a more secure location. Claire uncovers a shocking piece of information about the fate of the raft when the message bottled washes ashore.
Jack, Locke and Kate learn more secrets about the hatch. Meanwhile, after being beaten and taken captive, Sawyer, Michael and Jin wonder if their captors are fellow survivors or the dreaded “Others.”