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O'Quinn has long been a reliable character actor, playing recurring roles as authority figures on such shows as The West Wing, Millennium, JAG, Harsh Realm, and Alias, the J.J. Abrams-created series that led to O'Quinn's casting on Lost as island philosopher king John Locke. On film, his most memorable role has been the title character in the underrated 1987 thriller The Stepfather (shown). O'Quinn is alternatingly sympathetic and chilling as a serial killer who marries into ready-made families, then inevitably slaughters the new wife and kids when they fail to measure up to his rigid idea of family values. That ability to seem both fatherly and mysteriously menacing has served O'Quinn well on Lost.
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The character of con man Sawyer was written as a fast-talking New Yorker, but Georgia-born Holloway used his Southern drawl in his successful audition for the part. ''I just threw the [Buffalo] accent out the window,'' he told EW. ''I knew they'd laugh at me if I tried it.'' Surely the drawl was more impressive than Holloway's résumé, which consisted mostly of guest spots on such shows as CSI and Angel. Oh, and one memorable moment in the 1993 music video for Aerosmith's ''Cryin''' (shown), where he played the thief who makes the mistake of snatching Alicia Silverstone's purse and gets his butt kicked by the teen. Guess that was good practice for Sawyer's tussles with Kate and Ana Lucia.
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Daniel Dae Kim
Korean-born Kim, who plays expert fisherman Jin, grew up in the United States. Maybe that's how he landed a character with an all-American name like Tom Baker, the counter-terrorism agent he played as a recurring role for two seasons on 24. Baker didn't get to do much, though he did get to arrest Sherry Palmer (Penny Johnson Jerald, shown) in the season 2 finale. Kim had similarly thankless recurring roles on ER and Angel before he got his big break on Lost. ''I wish I could say that they were looking for me all over the globe,'' he told EW, ''but my agent got the call that they needed a Korean who could speak Korean, and I got the part.''
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Emilie de Ravin
Even before she landed the role of new mom Claire on Lost, de Ravin had appeared in several spooky, otherwordly projects, including the series BeastMaster, where she played a demon, and the TV remake of Carrie. But the Aussie actress' most prominent role was as Tess, the teenage alien vixen Roswell fans loved to hate. After she'd starred in the first two seasons (1999-2001) of the show's three-year run, fellow alien Max (Jason Behr, shown) impregnated her character, then abandoned her to fly off to a distant world and raise their sickly child on her own. Sound like any Flight 815 passengers you know?
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Perrineau nearly passed up the audition to play Michael, whose effort to rescue kidnapped son Walt has driven much of Lost's plot this season. He didn't want to drop out of a stage production of Topdog/Underdog but reconsidered when he heard he was Lost creator J.J. Abrams' first and only choice to play Michael. The versatile actor had enjoyed memorable roles in the The Edge, where he was eaten by a bear; Oz, where his paraplegic prisoner served as the narrator; and the Matrix trilogy, where he played a rebel who managed to survive to the last reel. But he may have been best known (at least among young girls) as Mercutio in Baz Luhrmann's gangland version of Romeo + Juliet, where his ill-fated Mercutio fought alongside Romeo (Leonardo DiCaprio, right). Like Michael, he was a guy who probably shouldn't have been allowed to handle a gun.
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Sexy fugitive Kate on Lost is Lilly's first Hollywood speaking role; before that, the little-known Canadian import had been an extra on such shows as Smallville and Tru Calling. But Lost creator J.J. Abrams liked what he saw when he came across a tape of Lilly. ''She was beautiful, but there was a goofy quality about her,'' he told EW, ''so it didn't feel like she wasn't a human being.'' Beautiful but goofy — was he watching her now-notorious commercial for LiveLinks, a romance chat line? Offscreen, Lilly has found romance on the island set with Lost costar Dominic Monaghan (Charlie).
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Before he won the role of Mr. Eko, Lost's mysterious drug dealer-turned-priest, the Nigerian-born Akinnuoye-Agbaje was a model, then an actor in such African-themed kitsch as Ace Ventura: When Nature Calls and Congo. His best known role, however, was on HBO's prison drama Oz (shown), where he played Simon Adebisi, a drug dealer who'd decapitated a cop, and whose murderous ways continued behind bars. (It's also where he costarred opposite future Lost castmate Harold Perrineau.) ''He's an African warrior,'' Akinnuoye-Agbaje said of Adebisi in an EW interview. ''He must win, he must be in control, and he has no fear. That's why he's not dead.'' Sounds a lot like the monster-confronting Eko.
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Before Garcia became famous for playing numbers-obsessed lottery winner Hurley on Lost, his steadiest gig was a character who tended to pursue get-rich-quick schemes. He was a costar on CBS' sitcom Becker during its sixth and final season (2003-04), playing Hector Lopez, a mooching slacker who spent a lot of time hanging out in a Bronx diner frequented by Dr. Becker (Ted Danson, left) and run by Chris Connor (Nancy Travis, right). But it was his scene-stealing guest spot as a drug dealer on Curb Your Enthusiasm that won over the Lost creators. In fact, Garcia was the first castaway to be cast. They didn't have a part for him, producer Damon Lindelof told EW, but they liked Garcia so much, ''we said, 'F--- it. Let's write a character for that guy!'' Dude!
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Andrews' heritage — he was born in London to Indian immigrant parents — has made him suitable for characters with all kinds of backgrounds, including Sayid, the former Iraqi Republican Guard torturer he plays on Lost. ''Recently, I've started thinking that most white people would give their left leg to play some of the complex, tortured parts I've gotten to play,'' he told EW. Those parts have included a Pakistani Londoner who starts a country band in Wild West (1992) and a 16th-century Indian prince in Kama Sutra: A Tale of Love (1996). But his best-known pre-Lost role was Kip, the Sikh lieutenant and bomb-defusing expert who falls for nurse Juliette Binoche (shown) at the tail end of World War II in The English Patient. These days, handling explosives, fixing radios and computers, and interrogating prisoners is all in a day's work for Andrews.