THEN: Bill Pullman played the President of the United States.

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He is perhaps best known for giving an epic speech.

NOW: Pullman has consistently acted since the first movie, but never had a role as iconic. He returns as a much more grizzled version of Whitmore in "Independence Day: Resurgence."

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THEN: Mae Whitman played the president's daughter, Patricia Whitmore.

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NOW: Whitman has become a cult favorite on TV. She first gained notice for playing George Michael's girlfriend on "Arrested Development." She then played Amber on "Parenthood" for six seasons.

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Whitman's character will be returning for "Resurgence." However, Whitman will not be. Maika Monroe will be playing adult Patricia Whitmore. In fact, Whitman was not even on the short list of actresses considered for the role, according to The Hollywood Reporter.

THEN: Margaret Colin played Constance Spano, the White House Communications Director and David's ex-wife.

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NOW: Colin played Eleanor Waldorf for six seasons on "Gossip Girl." She won't be in the "Independence Day" sequel.

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THEN: Mary McDonell played First Lady Marilyn Whitmore.

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NOW: McDonell was in the cult classic "Donnie Darko." She's also appeared in "Battlestar Galactica," "The Closer," and "Major Crimes." She won't be back for "Resurgence."

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THEN: Jeff Goldblum played computer wiz David Levinson.

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NOW: Goldblum has had a long, successful career in Hollywood. He's been in huge blockbusters ("Jurassic Park"), indie movies ("The Life Aquatic with Steve Zissou"), and TV shows ("Portlandia"). He's even become an internet meme.

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He'll reprise his role in "Resurgence" and will play Grandmaster in Marvel's upcoming "Thor: Ragnarok."

THEN: Judd Hirsch played rabbi Julius Levinson, Jeff Goldblum's "Independence Day" dad.

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Hirsch's career goes all the way back to the 1970s. One of his first big claims to fame was the immensely popular sitcom "Taxi," in which he played the lead.

NOW: Hirsch has made appearances in "The Goldbergs," "The Big Bang Theory," and "Maron," almost always playing someone's father. He's back for "Resurgence."

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THEN: Randy Quaid played pilot Russell Casse. This wasn't his first rodeo with a UFO.

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NOW: Nobody has had a stranger career turn than Randy Quaid. Despite an appearance in 2005's "Brokeback Mountain," the actor hasn't been in a movie since 2009, given his many run-ins with the law.

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Quaid and his wife Evi were first arrested in 2010 on suspicion of burglary and entering a building without consent. They have been living in Canada for the last few years. They made headlines in October 2015 when they were detained by border agents.

THEN: Harvey Fierstein played Levinson's boss Marty Gilbert. Unfortunately, Marty gets stuck in a traffic jam and doesn't make it out of New York alive.

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NOW: Fierstein, perhaps best known for his raspy voice, could be heard in "Mulan." He continues to star in movies, TV shows, and plays on Broadway.

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THEN: James Rebhorn played Secretary of Defense Albert Nimzicki.

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NOW: Rebhorn, a renowned character actor, passed away in 2014 at age 65. He appeared in movies like "Meet the Parents" and had notable roles on TV shows like "Homeland," "Enlightened," and "Law & Order."

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In a rare instance, Rebhorn wrote his own obituary, which was posted to his church's website.

"Jim was fortunate enough to earn his living doing what he loved. He was a professional actor. His unions were always there for him, and he will remain forever grateful for the benefits he gained as a result of the union struggle. Without his exceptional teachers and the representation of the best agents in the business, he wouldn’t have had much of a career. He was a lucky man in every way," Rebhorn wrote about his own life.

THEN: Brent Spiner was played the research director of Area 51, Dr. Brackish Okun.

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NOW: Spiner has had quite the career appearing in everything from "Star Trek" films as Data to lending his voice to "Star Wars Rebels." He'll be back in "Resurgence" and you can also see him on Showtime's upcoming series "Outcast."

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THEN: Vivica A. Fox played Captain Hiller's (Will Smith) girlfriend Jasmine Dubrow.

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NOW: Fox has proved she can play all kinds of role. She played the assassin Vernita Green in "Kill Bill" and went toe-to-toe with Larry David for a season on "Curb Your Enthusiasm." She's back for "Resurgance."

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THEN: Before "Independence Day," Will Smith was just a fresh prince living in Bel Air. He played Captain Steven Hiller, who memorably punches an alien in the face.

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After launching the first "Resurgence" trailer, Fox also announced that Smith's character was killed off. So it looks like we won't see him in any future sequels.

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NOW: This Smith guy has really gone places. Since "Independence Day" launched him to stardom, Smith has become one of the biggest movie stars in the world. While he won't be returning for "Resurgence," you'll be able to see him in this summer's "Suicide Squad."

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Smith turned down working on the film. 

When asked about why Smith wouldn't be returning for the sequel, director Roland Emmerich says the star is "too expensive."

"Will Smith can not come back because he's too expensive, but he'd also be too much of a marquee name," Emmerich told The New York Daily News in 2013. "It would be too much."