One of the castaways is chosen to descend into the mysterious hatch, and Shannon stumbles upon a shockingly familiar face in the jungle.

Michael and Sawyer fight for their lives on the high seas and discover a new threat. Locke descends into the hatch to find a missing Kate.

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."

Hurley struggles with a task inside the hatch as he flashes back to disturbing memories. Sawyer and the others learn their captors' identities.

Michael se dirige a la selva a buscar a Walt, pero descubre que él no está solo, Sawyer y Jin son organizados por sus captores para llevarlos a su campamento y Sun busca desesperadamente por su anillo de bodas.

Sawyer's wound becomes life threatening as he, Michael and Jin make their way across the island with the tail section survivors.

Forty-eight days ago, the tail section of Flight 815 crashes. The survivors struggle to live when some other people on the island continue to kidnap some of them.

Tempers flare when Ana Lucia and her group stumble upon Sayid and the other castaways.

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.

Claire loses faith in Charlie after Eko questions him about the Virgin Mary statues.

Jack, Locke and Sawyer follow Michael who left to look for his son. They meet "the others". More is shown about Jack's back-story.

When Charlie's dreams lead him to believe Claire's baby's in peril, Locke suspects he may be using drugs again. Charlie's back story reveals a difficult relationship with his brother. Hurley's encouraged to act on his attraction t...

Survivors fear that "The Others" may have returned after someone attempts to kidnap Sun. Sawyer is an amused, highly interested bystander when tension escalates between Jack, Locke, Kate, and Ana Lucia over control of the weapons ...

The mysterious French woman, Danielle Rousseau returns to lead Sayid to a mysterious captive who claims he crashed on the island. Meanwhile, Sawyer recruits Hurley to help him find another island animal that is harassing him: a lo...

When Claire's baby falls ill, she becomes determined to find out what happened to her and tries to regain her memory during her captivity with the Others. Mr. Eko learns about Henry Gale and requests a meeting with him.

When Sun finds out she's pregnant, she struggles on whether to tell Jin. Ana Lucia is called in by Locke to interrogate Henry Gale. Ana Lucia, Sayid, and Charlie then set out into the jungle to try and confirm Henry's story.

When the hatch suddenly takes on a life of its own, Locke is trapped and is forced to enlist the help of an unlikely ally. Jack faces off against Sawyer in a series of poker games for supplies. The truth about Henry is revealed.

Hurley thinks the island is affecting him in a strange way and starts recalling his past in a mental hospital with his friend Dave. Libby offers him support. Henry Gale reveals something to Locke, severely shaking his sense of pur...

Rose is opposed to Bernard's plan to build an SOS sign on the beach. Jack and Kate venture into the jungle to propose a trade with the Others.

Jack and Kate bring an exhausted Michael back to camp, where he gives them news about "The Others". Henry attacks Ana Lucia. Hurley plans a surprise date for Libby.

Mr. Eko enlists Locke's help to find a secret location he believes houses answers to the island's mysteries. Jack has a difficult, but unavoidable decision to make about Libby.

Michael's whereabouts during his 13 days in captivity in the "Others" camp are detailed. Back in the present, he tries to mount a search party for Walt, but his behavior makes Sayid suspicious.

After discovering a sailboat just offshore containing Desmond, Jack and Sayid come up with a plan to confront "The Others". Eko and Locke come to blows as Locke makes a potentially cataclysmic decision regarding the "button".

Jack, Kate, Sawyer, and Hurley are captured by the Others. Michael achieves his goal. Desmond realizes that Locke is wrong about the "button".