Chris Pine and Karl Urban in "Star Trek"
Photo: Paramount Pictures

BEVERLY HILLS, California — For two decades, the sacred realms of "Star Trek" and "Star Wars" ruled the sci-fi universe as two separate and distinct entities. Most people worshipped one or the other — and which one you chose spoke volumes about you.

"Star Trek," it was typically argued, was a scientific look at what the future could be — a brainy, sometimes dry depiction of humanity's endless quest to go where no man had gone before. When "Star Wars" was launched in 1977, it depicted an epic galaxy from long ago and far, far away; its over-the-top aliens and beaten-up spaceships were irreverent, action-packed and gritty.

But now that George Lucas has released three antiseptic prequels and self-professed "Star Wars" fan J.J. Abrams is unveiling his sleek, sexy new "Star Trek" movie this weekend, is the line being blurred? And is this a good thing?

"That was the fun of it," Abrams explained to us recently. "[I] was trying to combine both of those elements and make a movie that wasn't like a 'Star Wars' movie but felt that it had more pace and action than certain 'Star Trek' movies had."

Perhaps as a result, Captain Kirk is chased down on an ice planet by an enormous creature, Wampa-style. An early scene introduces Uhura at a bar populated by hard-drinking aliens. And in one key scene, the villain proves his ruthlessness by destroying the home planet of a key character.

"In our early conversations, [co-writer] Alex [Kurtzman] kept saying, 'We have to put a little "Star Wars" into our "Star Trek," ' " remembered Roberto Orci, who wrote the film with Kurtzman. "It was our chocolate and our peanut butter, kind of getting into each other."

It didn't take a Spock-like genius to figure out that the geek-embracing tone of "Trek" had grown stale by 2001/2002 — the period in which a movie ("Nemesis") and TV show ("Enterprise") were both released to bad reviews and an indifferent fanbase — while Lucas' franchise continued raking in hundreds of millions of dollars annually.

" 'Star Trek' has promised an adventure that it didn't always have the resources to deliver," Abrams said, saying that Lucas' financial success and independence couldn't be approached by the "Trek" franchise in those days. "So there was a lot of talk about stuff — which probably makes for more creative decisions, and you have to be smarter, more dramatic, and there's less of an easy way out — but you can't rely on spectacle."

"We're not going to lie to you: We were massive 'Star Wars' fans as much as we were 'Star Trek' fans," added Kurtzman, who said the three all agreed early on that "Trek" needed to be sleeker and faster for its reboot. "What I needed to see as an audience member now — given what I think audiences are used to — was a space battle that was about speed. And 'Star Wars' was always a little more about speed, a little more rock-and-roll than 'Trek.' "

Meanwhile, starting with 1999's "The Phantom Menace" and progressing through the new "Clone Wars" film and cartoon show, the "Star Wars" universe has traded in its rock-and-roll looseness for stiffer dialog, lifeless CGI sets and the sort of complicated story lines that used to be the hallmark of "Trek." To further blur the line between the two franchises, Abrams sought special-effects help from none other than the "Star Wars" mastermind himself.

"ILM, George Lucas' company, did the visual effects. They are incredible," Abrams gushed.

" 'Trek' was always about slow naval battles. ... What was really cool about 'Star Wars' was it was all about dogfights," Kurtzman said. "We thought, 'There has got to be a way to combine those two things.' "