The first "Alien" (1979) made a star of Sigourney Weaver, whose Ripley character returned in three sequels. Since appearing in "Alien: Resurrection" in 1997, Weaver has narrated the US version of the documentary series "Planet Earth" and reunited with "Aliens" director James Cameron for 2009's "Avatar."
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In the first film's bloodiest and most famous scene, John Hurt gave unexpected birth to an alien that burst from his chest. The British actor, who died in January 2017, went on to appear in "The Elephant Man," "V for Vendetta," "Indiana Jones and the Kingdom of the Crystal Skull" and the "Harry Potter" film series.
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Veteran character actor Harry Dean Stanton was one of the alien's first victims in the original movie. He has since appeared in dozens of films, including "Repo Man," "Pretty in Pink," "Paris, Texas," "Twister" and "The Green Mile." He also had a cameo in 2012's "The Avengers."
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British actor Ian Holm played Ash, the spaceship's science officer, who was revealed to be an android in the first film. Holm is probably best known for playing Bilbo Baggins in "The Lord of the Rings" movies.
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Originally a theater actor, Yaphet Kotto was cast in "Alien" after playing a Bond villain in "Live and Let Die." Kotto later played an FBI agent in the movie "Midnight Run" and a cop in the TV series "Homicide: Life on the Street."
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Comic actor Paul Reiser played against type as a villain in 1986's "Aliens." Best known for his role opposite Helen Hunt in the long-running sitcom "Mad About You," Reiser had a supporting role in 2014's "Whiplash."
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Lance Henriksen's craggy features and commanding voice have made him a fixture in action movies, TV and video games for decades. Since playing the android Bishop in "Aliens" and "Alien 3," he has appeared in the spinoff "Alien vs. Predator" and John Woo's "Hard Target." Henriksen also has lent his voice to such video games as "Call of Duty: Modern Warfare 2."
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Bill Paxton provided some rare comic relief as voluble soldier Hudson in "Aliens." He went on to appear in "Apollo 13," "Twister" and several other James Cameron films, including "True Lies" and "Titanic." He also starred as a polygamist in HBO's "Big Love." The actor died in February 2017.
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Michael Biehn played the Marines' heroic squad leader in "Aliens" and appeared fleetingly in "Alien 3." He has since had a variety of roles -- many of them as soldiers -- in movies, TV and video games.
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Charles S. Dutton played the leader of a penal colony in David Fincher's bleak "Alien 3" (1992). Since then, Dutton directed the HBO miniseries "The Corner," a precursor to "The Wire," and has appeared in such TV dramas as "Criminal Minds" and "The Good Wife."
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British actor Charles Dance played a doomed penal-colony doctor in "Alien 3." He is probably best known for his role as the ruthless lord Tywin Lannister in HBO's "Game of Thrones."
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Producers hoped Winona Ryder would help re-energize the franchise with 1997's "Alien: Resurrection," but the film was not a critical or commercial hit. Ryder's career stalled after a 2001 shoplifting arrest, although she has returned to the screen in such well-received vehicles as the Netflix series "Stranger Things" and films as "A Scanner Darkly" and "Black Swan."
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Dan Hedaya, who has built a long career playing crooks and slimeballs, had a short-lived part in "Alien: Resurrection." He had a supporting role in Barry Levinson's 2014 comedy, "The Humbling," with Al Pacino.
