Y'know, this was supposed to be Geek Dave's weekend off, but noooo.
1. The idea for Independence Day came about in 1994 when Roland Emmerich and Dean Devlin were in Europe promoting their film Stargate. Emmerich had gone on record stating he did not believe in aliens, so a reporter asked him why he would make a film with content like Stargate. Emmerich replied that he was still fascinated by the idea of an alien arrival, and further explained his response by asking the reporter to imagine what it would be like to wake up one morning and discover 15-mile-wide spaceships were hovering over the world's largest cities. Emmerich then turned to Devlin and said, "I think I have an idea for our next film."
2. After they finished their promotional tour for Stargate, Emmerich and Devlin took a month long vacation in Mexico where they wrote the script for Independence Day, and just one day after they sent it out for consideration, 20th Century Fox chairman Peter Chernin greenlit the production.
3. There was one sticking point, Warner Bros. owned the rights to the title Independence Day. So during production the film was nicknamed ID4, however both Emmerich and Devlin were determined to make sure 20th Century Fox would do everything they could to secure the use of Independence Day.
Just before Bill Pullman was to film his pre-battle speech, Devlin pulled the actor aside, and together they decided to add "Today, we celebrate our Independence Day!" to the end of the speech. Devlin said he hoped that when Fox executives noticed the addition in dailies, the impact of the new dialogue would give them extra encouragement to win the rights to the title. It worked! Two weeks later the title was secured.
4. The U.S. military originally intended to provide personnel, vehicles, and costumes for the film; however, they backed out when they discovered the Area 51 references in the story.
5. Independence Day used the same White House interior sets which had been built for the 1995 Michael Douglas film The American President, and had previously been used for Nixon.
6. One day during the shoot Roland Emmerich was notified that Robert Loggia was very upset and refusing to leave his trailer. Earlier, Loggia had spoken with Dean Devlin, asking for inspiration in how to approach his character, General William Grey, and in what context his scenes would appear.
Devlin intended to suggest to Loggia that he watch the 1970 disaster movie Airport, but either the producer mistakenly suggested the wrong title, or Loggia's assistant was confused because the film he was given was 1980's comedy Airplane! Not familiar with either movie, Loggia knew no better, and after watching it thought that he had unknowingly been duped into participating in the production of a "spoof" movie.
7. Matthew Perry was originally set to play the role of Captain Jimmy "Raven" Wilder, but had to pull out at the last minute, being replaced by Harry Connick Jr. Perry's father, John Bennett Perry, plays a secret serviceman in the movie.
8. Many of the actors were encouraged to improvise their dialogue around the particular scene they were in, so much so that Devlin later revealed that well over half of the dialogue in the scenes Jeff Goldblum shared with Judd Hirsch and Will Smith was entirely improvised.
9. Another unscripted moment came about during the scene in which Will Smith drags the unconscious alien across the desert, and Smith says "And what the hell is that smell?". The scene was filmed on the salt flats near Great Salt Lake in Utah, an area home to tiny crustaceans called brine shrimp. When they die, their bodies sink to the bottom of the shallow lake and decompose, and when the wind kicks up just right the bottom mud is disturbed, releasing the disgusting odour of millions of decaying brine shrimp. That was the smell Will Smith was referring to.
10. While Independence Day was still in post-production, 20th Century Fox began a massive marketing campaign to help promote the film, beginning with the airing of a dramatic commercial during Super Bowl XXX, for which Fox paid $1.3 million. It was Independence Day's subsequent success at the box office which resulted in the trend of using Super Bowl commercials to kick off the advertising campaign for potential blockbusters.
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