"We will not go quietly into the night! We will not vanish without a fight!" insists Bill Pullman in Independence Day, the rah-rah sci-fi blockbuster that blew up both the White House and the box-office in 1996. But unlike its characters, Independence Day performed a strange kind of vanishing act; ever since Will Smith, Bill Pullman, and company rallied and fought back their alien adversaries, the seemingly surefire franchise has remained curiously (and for Hollywood, uncharacteristically) silent.

Independence Day was the highest-grossing movie of 1996 by a considerable margin, earning more than $800 million in an era before inflated ticket prices. It remains the highest-grossing film in the careers of both director Roland Emmerich and star Will Smith, and many credit it with kicking off Smith's career as an A-List Hollywood actor. In this franchise-happy cinematic climate, how is it possible that we haven't had an Independence Day sequel?

As it turns out, it's not for lack of trying. Emmerich and his co-writer/producer Dean Devlin have been working on a sequel in some form or another for more than a decade, and their efforts have paid off: The duo are simultaneously working on two follow-ups optimistically titled ID Forever Part I and Part II. (Part I will reportedly hit theaters in 2015). In a 2002 interview, Devlin spoke about the difficulty of making an Independence Day sequel. "I like to think that hit movies are like a cocktail, you know?" he said. "You want to try to get all the ingredients back together again and try to get the same mix."

Unfortunately, that cocktail will be missing one of its primary components: Smith, who will not be reprising his starring role from the film. In 2009, Devlin told Latino Review that Fox wanted to make the sequels without Smith, deeming his reported $50 million salary too expensive. "Will is essential for us, for this movie and actually for the audience too," Devin insisted — but apparently not essential enough to keep the sequels from being produced without him.

While it's a fairly safe bet that ID Forever will be about aliens, both Emmerich and Devlin have been coy about the films' plot lines. In 2002, Devlin described a sequel, inspired by the 9/11 terrorist attacks, that would focus on "how the world came together in the aftermath" of the Independence Day invasion. In March, Emmerich said the sequel would focus on the stepson of Will Smith's character, who will square off against the aliens after they reemerge from a wormhole. Jeff Goldblum and Bill Pullman are both slated to return in supporting roles, and Emmerich is still holding out hope that he can convince Smith to show up for a cameo.

Which leaves one key question: Do audiences actually care about Independence Day anymore? A planned re-release of Independence Day in 3D might have helped audiences remember why they liked the movie in the first place — and introduced it to a whole new audience — but 20th Century Fox scrapped those plans late last year. In Hollywood, 19 years is a staggeringly long gap between a film and its sequel, and the interim has seen Emmerich relentlessly peddling his "more is more" blockbuster shtick in movies like Godzilla, The Day After Tomorrow, 2012, and last week's White House Down — a film that has turned out to be a major financial disappointment. (Especially for a director whose all-time most recognizable scene hinged on blowing up the White House.)

"Today we celebrate our Independence Day!" finishes Bill Pullman in the speech that gives Independence Day its name. The burgeoning franchise's path to inevitable sequel-hood has been longer and stranger than the average blockbuster, but it sounds like we'll actually, finally be welcoming the sequels to Earth in the near future — if audiences still care enough about Independence Day to celebrate it.