Lost

Naveen Andrews as Sayid Jarrah
A former military communications officer, Sayid is haunted by his past as an interrogator for the Iraqi Republican Guard. On the island, he is romantically involved with Shannon. After escaping the island and coming to America, he reunites with and marries his former girlfriend Nadia. After Nadia is murdered, Sayid is employed by Ben as an assassin to kill the associates of Charles Widmore.

Matthew Fox as Dr. Jack Shephard
A spinal surgeon with father issues, Jack is the survivors' leader. He has feelings for Kate. After escaping the island, he ends up in a relationship with Kate but after a dramatic breakup he becomes drug-addicted and suicidal because he longs to return to the island to save everyone left behind, and return to his relationship with Kate.

Jorge Garcia as Hugo "Hurley" Reyes
After winning the lottery with the numbers, Hurley suffers from great bad luck. He remains optimistic on the island but after escaping from it is hospitalized for psychiatric reasons that include recurring hallucinations involving Charlie.

Josh Holloway as James "Sawyer" Ford
James is a confidence man who was orphaned as a child when his father killed his mother - and himself - after his mother was conned for all their money by a man named Sawyer. All that James knows about the man who conned her is his name, and he adopts this name - Sawyer - for himself, and goes on to con various women for hundreds of thousands of dollars when he grows up. With Cassidy, one of these women, he has a daughter named Clementine whom he has never met. He travels to Australia to kill the man he believes is the original Sawyer, but he is wrong and kills an innocent man. On the Island, he is initially disliked for his antisocial behaviour and for his practice of nicknaming his fellow survivors, but he becomes romantically involved with Kate and, eventually, friendly with the rest despite his rough personality. When John moves the island and the remaining survivors are launched back into the 1970s, Sawyer joins the Dharma Initiative under the name Jim LaFleur, and he becomes head of security due to his ability to deal with the Hostiles. He falls in love with Juliet, and they are living together three years later. He, Juliet and Kate are evacuated on the Dharma submarine when Daniel alerts Dr. Chang to the "Incident."

Daniel Dae Kim as Jin-Soo Kwon
The son of a poor fisherman, Jin marries Sun on the condition that he work for her father as a mob enforcer. On the island, Jin struggles as the only castaway who does not speak English, although he does eventually begin to learn. He is presumed dead by his wife, Sun-Hwa Kwon, and the other members of the Oceanic Six, when a bomb goes off on the Kahana. Kwon is later found unconscious on driftwood by a French research team in 1988, having flashed to that time period with the other people on the island.

Yunjin Kim as Sun-Hwa Kwon
The rich daughter of a hotel owner/automobile manufacturer with ties to the Korean mob, Sun has an affair and almost leaves her husband Jin before the crash. They reconcile on the island and she becomes pregnant with Jin's baby. After escaping the island, Sun gives birth to Jin's baby, a girl named Ji Yeon, off the island. With the settlement money from Oceanic, Sun buys a controlling share of her father's company.

Evangeline Lilly as Katherine Anne "Kate" Austen
After killing her abusive stepfather (later revealed to be her real father), Kate goes on the run and is eventually captured by a federal marshal while in Australia. On the island, Kate is attracted to both Sawyer and Jack, and eventually has a short relationship with Sawyer. After escaping the island, she is put on trial for murder, but subsequently makes a highly favorable plea bargain that does not require prison time. She becomes engaged to Jack and raises Claire's son Aaron as her own, pretending to be his biological mother as part of the Oceanic 6 cover story. Before Sawyer jumped out of the helicopter that would have brought him to safety with her, Sawyer whispered something in Kate's ear, which she will not reveal to Jack. His jealousy becomes the demise of their relationship. She resists returning to the island, but eventually decides that she will. She arrives on the island in 1977 and joins the Dharma Initiative, along with Jack and Hurley.

Terry O'Quinn as John Locke
After having his paralysis healed during the crash, Locke lives out his dreams of becoming a hunter on the Island. John Locke is also the name of a philosopher. Being a man of faith, he believes he has a special connection with the island, leading him to clash with man-of-science Jack. Having been "chosen," Locke becomes the leader of the Others at the end of the fourth season. Locke is eventually murdered by Ben shortly after leaving the island. When most of the "Oceanic Six" survivors return to the island, they transport Locke's body with them. Locke apparently returns to life, but this is revealed to be a deception; Locke is still dead, and the individual in Locke's form is actually Jacob's rival.

Emilie de Ravin as Claire Littleton
Claire gives birth on the island to a boy and forges a strong relationship with Charlie. She is also Jack's half-sister. She is not aware of this, but Jack learns this from her mother after he leaves the Island. Claire is later seen in Jacob's hut with her father. Her current whereabouts and her state of being are currently unknown.

Dominic Monaghan as Charlie Pace
A one-hit wonder, rock musician Charlie ends his addiction to heroin on the island and cares for Claire and her baby. He drowns in the Looking Glass station, trying to help the survivors communicate with the outside world.

Harold Perrineau as Michael Dawson
Michael is a New York artist and construction worker who has not communicated with his son Walt since he was a baby. When Walt's mother dies in Australia, Michael comes to collect his son (and Walt's dog, Vincent). Michael is the first on the island to learn that Sun speaks English, and he has various conflicts with Jin. While trying to escape the Island via raft, Michael's son Walt is abducted by the Others. Michael strikes a deal with the Others wherein he exchanges Kate, Jack, Sawyer and Hurley for Walt, and together the two leave the island by boat. However, when they return home, Walt goes to live with his grandmother after finding out that Michael killed Libby and Ana Lucia while carrying out his part of the deal. Michael tries to commit suicide a couple times but soon finds out that "the island won't let him die". He later infiltrates the Kahana freighter crew under the orders of Ben, in the hopes of making up for the lives he took by saving those of the people left on the island. He is killed in an explosion on the Kahana while trying to deactivate a bomb.

Maggie Grace as Shannon Rutherford
Shannon is a ballet instructor and Boone's stepsister. She has a relationship with Sayid on the island. She is accidentally shot and killed by Ana Lucia on the Island.

Malcolm David Kelley as Walter "Walt" Lloyd
An elementary school student, he is kidnapped by the Others, who claim that he is "special." He is rescued by his father Michael and goes to live with his grandmother in New York.

Ian Somerhalder as Boone Carlyle
Boone is the stepbrother of Shannon, with whom he is in love. On the island, he spends much of his time hunting with Locke, and together they find the first hatch. He slowly learns that Shannon is manipulative and does not love him, but he remains protective of her. When John's legs mysteriously malfunction, Boone climbs into a crashed plane, perched in a tree, and uses its radio to contact (although he doesn't know it) the tail section survivors. The plane falls with Boone in it, and his leg and torso are crushed. John carries him back to the camp to be treated by Jack and Sun, but Boone dies shortly thereafter.

Adewale Akinnuoye-Agbaje as Mr. Eko
Mr. Eko is a former Nigerian drug lord turned priest who crashes on the island with the tail section survivors. For the first 40 days, he does not speak. Upon joining the fuselage survivors' camp, Eko becomes part of the group involved in pressing a button in a hatch. He begins building a church on the island with Charlie, but this is abandoned when he becomes obsessed with the hatch and the button within. Eko is haunted by visions of his brother, who died in Nigeria and whose body was on a plane that crashed on the island before Eko's arrival. These visions lead Eko and John to discover another Dharma station. Eko meets the smoke monster on more than one occasion in the Island's forests, and is eventually killed by it.

Michelle Rodriguez as Ana Lucia Cortez
A former LAPD police officer, Ana Lucia is the leader of the survivors of the tail section of Flight 815. She loses her job as a police officer after killing the man who had previously shot her, killing her unborn child. She meets Christian at LAX and agrees to accompany him to Australia. Before the flight back to L.A. she chats up Jack, whom she doesn't know is Christian's son, at the airport bar. Ana Lucia is very protective of her fellow survivors after several are kidnapped, and she is extremely distrusting of others. She eventually kills Goodwin after discovering that he is not a survivor of the crash. She also inadvertently kills Shannon. Ana Lucia is shot and killed by Michael Dawson while he tries to free Ben, the leader of the "Others," but she appears after her death in visions to several of the characters, notably Hurley.

Cynthia Watros as Elizabeth "Libby"
Libby is a tail section survivor. Prior to the crash of 815, she met Desmond and gave him her late husband's boat for the around the world race that ended with Desmond crashing on the island. She is also revealed to have been a patient in the same mental institution at the same time as Hurley. She becomes romantically involved with Hurley. She is shot to death by Michael after accidentally witnessing Ana Lucia's death.

Michael Emerson as Benjamin Linus
Ben is the manipulative leader of the Others. He is captured by the survivors and is held hostage in a hatch that Boone and Locke found. However Michael releases him in return for the safe passage of himself and his son, Walt, back home. In the finale of the 4th season he is forced to leave the Island after he "moves" it. He returns to the island in the fifth season with the Oceanic 6, to be judged by the mysterious smoke monster for letting his daughter die. The monster lets him live as long as he follows John which results in him killing Jacob.

Henry Ian Cusick as Desmond David Hume
Desmond, a former monk and member of the Royal Scots Regiment, undertakes a boat race around the world after splitting with his girlfriend Penny Widmore. He shipwrecks on the island while on this race, and he lives in a hatch for three years, pressing a button every 108 minutes. One day he neglects to push the button, and on this day Flight 815 crashes. The survivors find the hatch and blow it open, and when they take over pushing the button he attempts (unsuccessfully) to escape the island. After he returns to the island, he moves in with the crash survivors. At the start of the third season, Desmond starts seeing flashes of future events, most of them being about Charlie's death. Later, he experiences flashes into the past. He escapes the Island with the Oceanic Six at the end of season four and is reunited with his girlfriend, Penelope Widmore. They are married and have a baby boy named Charlie. Desmond has various meetings with Eloise Hawking who urges him not to marry Penny Widmore. He later finds out she is Daniel Faraday's mother, locates her through Charles Widmore, and visits her at the Lamppost.

Elizabeth Mitchell as Juliet Burke
Juliet is a fertility doctor recruited by the Others. She develops a relationship with Goodwin, who is killed by Ana Lucia, and Juliet blames Ben. Ben is in love with her and refuses to let her leave the island - and he orchestrated Goodwin's death out of jealousy. Although Juliet acts initially as Jack's interrogator when he, Sawyer and Kate are captured, she helps them and escape and joins the Oceanic 815 crash survivors. She defies Ben's orders to infiltrate the survivors' camp, and she has clear romantic feelings for Jack. She is left behind when the Oceanic Six leave the island, and when the recurring time flashes leave Juliet and the others in the mid-1970s, she becomes a mechanic for the Dharma Initiative and starts a relationship with Sawyer.

Kiele Sanchez as Nikki Fernandez
Nikki is an actress who, with her boyfriend Paulo, murders a television producer for his diamonds. When they get to the island they spend their time searching for the diamonds lost in the crash. She is assumed dead on the island after being buried alive, the survivors having assumed she was dead following a paralyzing spider bite.

Rodrigo Santoro as Paulo
Paulo helps Nikki murder a television executive for his diamonds. He spends his time on the island with Nikki searching for the diamonds. He is assumed dead on the island after being buried alive, the survivors having assumed he was dead following a paralyzing spider bite.

Jeremy Davies as Daniel Faraday
Faraday is a physicist hired to go to the Island by Charles Widmore. He initially claims to have intentions to save the 815 crash survivors, but this proves to be untrue. Daniel is connected to Desmond in several ways - Desmond visits him at Oxford during a flashback in time. Later, when John moves the island, Daniel travels back in time and visits Desmond in the hatch, to tell him how to save the island. Even though he initially lied about his intent to save the survivors, Daniel ends up ferrying several of them, including Sun and Jin, to the Kahana. He is the son of Eloise Hawking and Charles Widmore.

Ken Leung as Miles Straume
Miles is a spiritualist hired by Charles Widmore to go to the Island. He has the ability to read the final thoughts of the deceased. He has the most cutting wit out of the Kahana away team members, earning him a comparison to Sawyer by Hurley. It is later revealed that he is the son of Dr. Pierre Chang.

Rebecca Mader as Charlotte Staples Lewis
Charlotte is an anthropologist hired to go to the Island by Charles Widmore. Miles suggests that she has been to the Island before and she chooses to stay there when given the option to leave. She later dies due to the ill effects of the Island's erratic movements through time and admits she was born on the Island, her parents being members of the Dharma Initiative.