- "A Tale of Two Cities"
Jack, Kate and Sawyer begin to discover what they are up against as prisoners of "the Others".
- "The Glass Ballerina"
Sayid's plan to locate Jack places Sun and Jin's lives in grave danger. Meanwhile, Kate and Sawyer are forced to work in harsh conditions by their captors, and Henry makes a very tempting offer to Jack that may prove difficult to refuse.
- "Further Instructions"
The fates of Locke, Eko and Desmond are revealed after the implosion of the hatch, while Hurley returns to the beach camp to tell the tale of what happened when he, Jack, Kate and Sawyer encountered "The Others".
- "Every Man for Himself"
Sawyer discovers just how far his captors will go to thwart any plans of escape he and Kate might have, and Jack is called upon to scrub up in order to save the life of one of "The Others". Meanwhile, Desmond's behavior begins to perplex the survivors when he starts construction on an unknown device.
- "The Cost of Living"
A delirious Eko wrestles with demons from his past, while Locke and some of the other castaways head back to The Pearl -- one of the DHARMA Initiative's island stations -- hoping to find a computer that they can use to locate Jack, Kate and Sawyer. Meanwhile, Jack doesn't know whom to trust when two of "The Others" seem at odds with one another.
- "I Do"
Jack makes a decision regarding Ben's offer, Kate feels helpless when it looks like an angry Pickett is going to make good on his threat to kill Sawyer, and Locke discovers a hidden message that may guide him through the next steps of his journey to unlocking the secrets of the island.
- "Not in Portland"
Jack is in command as the fate of Ben's life literally rests in his hands. Meanwhile, Kate and Sawyer find an ally in one of "The Others", and Juliet makes a shocking decision that could endanger her standing with her people.
- "Flashes Before Your Eyes"
A suspicious and determined Hurley enlists Charlie to help him wrangle the truth out of Desmond, who has been acting strangely ever since the implosion of the hatch.
- "Stranger in a Strange Land"
A power play ensues between Jack and "The Others" as Juliet’s future hangs in the balance. Meanwhile, Kate, Sawyer and Karl continue on their journey away from "Alcatraz".
- "Tricia Tanaka Is Dead"
Hurley’s discovery of an old, wrecked car on the island leads him on a mission of hope not only for himself, but for a fellow survivor in need of some faith. Meanwhile, Kate and Sawyer reunite with their fellow castaways, but Kate is still torn about leaving Jack behind with "The Others".
- "Enter 77"
Locke, Sayid and Kate investigate a strange structure and its mysterious inhabitant. Meanwhile, Sawyer competes in a ping-pong competition to get back his belongings.
- "Par Avion"
Claire becomes suspicious of Charlie when he exhibits peculiar behavior after she comes up with an idea that could get everybody rescued. Meanwhile, tensions mount between Sayid and Locke as they continue their trek to rescue Jack.
- "The Man from Tallahassee"
Ben tries to persuade a determined Locke to call off his destructive plan by offering him some of the secrets of the island, and Kate's reunion with Jack does not go off as planned when she discovers that he has made a deal with "The Others".
Hurley begins to suspect that Sawyer may be involved in an island mystery surrounding two fellow survivors, and Sun learns the truth about her past kidnapping attempt by "The Others".
- "Left Behind"
After discovering that one of her own has betrayed her to "The Others", Kate is left to fend for herself in the jungle with Juliet. Meanwhile, Hurley warns Sawyer to change his selfish ways and make amends with his fellow survivors or he may face a vote of banishment.
- "One of Us"
Jack's joyous reunion with his fellow survivors is cut short when they realize that accompanying him is one of "The Others," and Claire is stricken by a mysterious, life-threatening illness
Desmond coaxes Charlie, Hurley and Jin on a trek across the jungle after experiencing one of his future-prophesizing flashes -- but is he purposely placing Charlie’s life in harm’s way? Meanwhile, Kate turns to an unwitting Sawyer after seeing Jack alone with Juliet.
After discovering that all of The Others pregnant women died before giving birth on the island, an extremely reticent Sun allows Juliet to examine her -- and uncovers the identity of the unborn child's father. Meanwhile, Desmond allows an unlikely nemesis to help save the life of a new, mysterious island inhabitant.
- "The Brig"
A newly focused Locke breaks away from "The Others" in an attempt to persuade Sawyer to help rid them of a great nemesis that has caused nothing but pain in both of their lives. Meanwhile, a new island inhabitant discloses some shocking information about Oceanic Flight 815.
- "The Man Behind the Curtain"
Ben begrudgingly begins to introduce Locke to the secrets of the island, beginning with the mysterious Jacob. Meanwhile, Juliet's secret goes public.
- "Greatest Hits"
While Jack devises a plan to do away with “The Others” once and for all, Sayid uncovers a flaw in “The Others’” system that could lead to everyone’s rescue. But it requires Charlie to take on a dangerous task that may make Desmond’s premonition come true.
- "Through the Looking Glass"
Jack and the castaways begin their efforts to make contact with Naomi's rescue ship.