Pilot (Part 1)
Survivors of a plane crash find themselves on a mysterious tropical island.
Pilot (Part 2)
The survivors organize and make a shocking discovery via a radio transmission.
Tabula Rasa
Jack discovers Kate's secret past. The marshal struggles to survive.
Walkabout
Locke goes on a boar hunt. His backstory reveals a life-changing secret.
White Rabbit
Jack chases a vision into the jungle while the survivors face a water crisis.
House of the Rising Sun
Sun's hidden talent is revealed. The survivors debate moving to the caves.
The Moth
Charlie struggles with his addiction. Jack is trapped in a cave collapse.
Confidence Man
Sawyer is suspected of hoarding medicine. His backstory reveals a troubled origin.
Solitary
Sayid encounters the woman behind the distress signal.
Raised by Another
Claire has disturbing dreams. A stranger among the survivors is discovered.
All the Best Cowboys Have Daddy Issues
Jack and Kate search for kidnapped survivors. A major discovery is made underground.
Whatever the Case May Be
Kate and Sawyer fight over a mysterious briefcase. Shannon helps translate maps.
Hearts and Minds
Boone and Shannon's complicated relationship is explored.
Special
Michael and Walt's strained relationship is tested. Walt may have unusual abilities.
Homecoming
Claire returns with no memory. The survivors prepare for Ethan's return.
Outlaws
Sawyer hunts a boar that seems to be targeting him. A drinking game reveals secrets.
...In Translation
Jin's perspective on his marriage to Sun is revealed. The raft is sabotaged.
Numbers
Hurley recognizes a sequence of numbers on Rousseau's maps and becomes obsessed.
Deus Ex Machina
Locke and Boone work to open the Hatch. Locke's tragic family history is revealed.
Do No Harm
Jack fights to save a life while a new life arrives on the Island.
The Greater Good
Sayid investigates Locke's role in Boone's death. Tensions rise.
Born to Run
Kate tries to secure a spot on the raft. Someone poisons Michael.
Exodus (Part 1)
Rousseau arrives with a warning. The raft launches. The expedition to the Black Rock begins.
Exodus (Part 2)
The first season reaches its climax. The raft encounters danger. The Hatch is opened.
Exodus (Part 3)
The aftermath of the season's climactic events.