Parent & Child

Jack Shephard

Played by Matthew Fox

A spinal surgeon who becomes the reluctant leader of the crash survivors. Driven by a need to fix everything and everyone. His journey from man of science to man of faith is the emotional spine of the entire series.

Kate Austen

Played by Evangeline Lilly

A fugitive who was being escorted back to the US by a federal marshal when the plane crashed. Resourceful and tough, she runs from her past but can't escape the connections she forms on the Island.

John Locke

Played by Terry O'Quinn

A man with a mysterious past who seems reborn on the Island. A hunter, a believer, and a man searching for purpose. His unwavering faith in the Island's meaning drives the show's central philosophical conflict.

Benjamin Linus

Played by Michael Emerson

The enigmatic and manipulative leader of the Others. Originally introduced as "Henry Gale," a supposedly stranded balloonist. Michael Emerson's portrayal turned a planned three-episode guest role into one of TV's greatest villains.

Jin-Soo Kwon

Played by Daniel Dae Kim

A Korean man initially perceived as controlling and cold, who gradually reveals himself to be a devoted husband navigating impossible circumstances. His arc from perceived villain to beloved hero is one of the show's best reversals.

Sun-Hwa Kwon

Played by Yunjin Kim

A Korean woman who secretly speaks English, trapped in a difficult marriage to Jin and under the shadow of her powerful father. Her quiet strength and determination make her one of the most formidable survivors.

Claire Littleton

Played by Emilie de Ravin

A young Australian woman who was eight months pregnant when the plane crashed. Fiercely protective of her unborn child. Her transformation from vulnerable expectant mother to feral Island survivor is one of the show's most dramatic character shifts.

Walt Lloyd

Played by Malcolm David Kelley

A young boy with mysterious abilities who was traveling with his estranged father Michael when the plane crashed. The Others' intense interest in Walt drives one of the show's earliest and most compelling mysteries.

Michael Dawson

Played by Harold Perrineau

A construction worker and aspiring artist desperate to reconnect with his son Walt after years of estrangement. His desperation to save Walt leads him to commit one of the most shocking betrayals in the show's history.

Charles Widmore

Played by Alan Dale

A powerful and ruthless magnate who was once the leader of the Others. Exiled from the Island by Ben, he spends decades trying to return. His rivalry with Ben is one of the show's longest-running power struggles.

Penny Widmore

Played by Sonya Walger

The woman Desmond loves. Daughter of Charles Widmore, she spends years searching for Desmond after he disappears sailing around the world. Their phone call in "The Constant" is one of the most emotionally powerful scenes in television.

Danielle Rousseau

Played by Mira Furlan

A French scientist who has been stranded alone on the Island for sixteen years. Her distress signal has been playing on a loop since her team was killed. Mira Furlan brings a haunted intensity to the role of the Island's loneliest inhabitant.

Alex Rousseau

Played by Tania Raymonde

Danielle Rousseau's daughter, stolen at birth and raised by Ben as his own. A rebellious teenager who often helps the survivors against the Others. Her execution by Keamy is one of the series' most shocking and pivotal moments.

Eloise Hawking

Played by Fionnula Flanagan

A mysterious woman who understands the rules of time. Former leader of the Others and guardian of the Lamp Post station, a DHARMA facility that locates the Island. Her burden of knowing she will kill her own son makes her one of the show's most tragic figures.

Jacob

Played by Mark Pellegrino

The ageless protector of the Island. He has been bringing people to the Island for centuries, searching for someone to prove that humanity is worthy and to replace him. Mark Pellegrino brings a serene, almost unsettling calm to the role of a 2,000-year-old guardian.

The Man in Black

Played by Titus Welliver / Terry O'Quinn

Jacob's twin brother, transformed into the Smoke Monster after being thrown into the Heart of the Island. He has spent millennia trying to leave the Island and will manipulate anyone to achieve it. The reveal that the Smoke Monster, the visions of dead people, and the Man in Black are all the same entity recontextualizes the entire series.

Pierre Chang

Played by Francois Chau

A DHARMA Initiative astrophysicist known to viewers through the orientation films where he uses aliases like Marvin Candle, Edgar Halliwax, and Mark Wickmund. His multiple aliases and prosthetic arm made him one of the show's earliest recurring mysteries.

Miles Straume

Played by Ken Leung

A sarcastic ghostbuster who can communicate with the dead. Arrives on the freighter but becomes a loyal member of the survivor group. Ken Leung's deadpan delivery makes Miles one of the show's sharpest comic presences.

Pilot (Part 1)

Survivors of a plane crash find themselves on a mysterious tropical island.

Walkabout

Locke goes on a boar hunt. His backstory reveals a life-changing secret.

Deus Ex Machina

Locke and Boone work to open the Hatch. Locke's tragic family history is revealed.

Live Together, Die Alone (Part 2)

The season finale. The button's truth is tested. Michael makes his choice.

The Candidate

The group tries to escape on the submarine. Devastating losses occur.