SAN FRANCISCO (AFP) - A long time ago in a galaxy far, far away, fans had to wait years between “Star Wars” movies -- but the space saga is back with the most hotly anticipated spinoff in cinema history.

Just 12 months after “The Force Awakens” shattered numerous box office records, Lucasfilm is unleashing “Rogue One: A Star Wars Story” as an early Christmas gift for its millions of devotees.

With just a week to go before its Dec. 16 US release, excitement is building for the eighth installment in George Lucas's sci-fi saga, which recorded the second-highest first day of domestic presales ever (behind “The Force Awakens”).

The job of building on Lucas’s legacy falls to British filmmaker Gareth Edwards, who recalled the nerve-jangling moment when the legendary director called him to deliver his verdict on the film after a preview screening.

“I don't want to put words into his mouth, but I can honestly say that I can die happy now,” Edwards said as he relived last week’s telephone conversation with Lucas, one of the most financially successful filmmakers in history.

Edwards -- addressing the world's media at Industrial Light and Magic, Lucasfilm’s special effects studio in San Francisco -- described how it was the one green light he could not live without.

“To be honest -- and no offense to anyone here -- it was the most important review to me, what George thought of it. You know, you guys are important too, but come on -- he‘s kind of God,” he told a room of critics.

“Rogue One” is part of an attempt to revitalize the franchise since Disney bought Lucasfilm in 2012, when it was still reeling from grim reviews for the much-maligned 1999-2005 prequel trilogy.

The idea was to bring out a sequel trilogy with a movie every other year -- starting with “The Force Awakens” in 2015 -- and intersperse those releases with an “anthology trilogy” of one-off, standalone movies in the even years.

‘Talking in corsets’

The 41-year-old Edwards -- who most recently made “Godzilla” (2014) after dazzling critics with his directorial debut, lo-fi creature feature “Monsters” (2010) -- is among a new wave of “auteurs” handpicked to ensure the strategy succeeds.

J.J. Abrams got off to a good start with “The Force Awakens,” which made $2 billion to become 2015’s biggest release, not to mention the most successful Disney motion picture and the third-highest grossing movie of all time.

Analysts expect “Rogue One” to open at up to $150 million, a bit behind the $248 million debut weekend for “The Force Awakens,” but still among the top releases this year.

Set just before “A New Hope” -- the original 1977 film -- it stars Felicity Jones as rebel Jyn Erso opposite rebel intelligence officer Cassian Andor, played by Diego Luna.

Jyn -- a delinquent with a string of convictions for forgery, assault and theft -- is recruited by the Rebel Alliance for a mission to destroy a planet-sized weapon of mass destruction that would later become known as the Death Star.

“I'd never done that kind of thing before so it was very new, the whole physical preparation side of acting,” said Jones, who was nominated for an Oscar for 2014 Stephen Hawking biopic “The Theory of Everything.”

“I’m used to lots of talking in corsets so it was really nice to be running around with a blaster and a baton to bash Stormtroopers with.”

War movie

Critics treated to a 28-minute preview at Lucas's Skywalker Ranch near San Francisco over the weekend noted that “Rogue One” eschews the “space opera” aesthetic of its predecessors in favor of the grittier look of a war film.

“We essentially got a license to be different on this movie and take a risk,” said Edwards, who believes his installment -- filmed in Britain, Iceland, Jordan and the Maldives -- is closest in tone to “The Empire Strikes Back” (1980).

To set out the raw look of the movie, the crew took real combat photographs from Vietnam and World War II and Photoshopped in rebel weapons and garb, with X-Wing fighters spliced into the background.

“The studio loved it, everyone loved it, and they said, ‘Go and make that,’ and that’s kind of what we went and did,” Edwards said.

It's not all doom and gloom, of course, and much of the film’s lighter moments come from Alan Tudyk, who had the unenviable task of having to follow much-loved characters C3PO, R2D2 and BB-8 into the “Star Wars” robot family.

The actor wore stilts and a full-body motion-capture jumpsuit to play K-2SO, an Imperial enforcer droid with attitude that has had its memory wiped by the rebels.

“The first month we couldn't look at him because he just looked ridiculous,” said Luna.

“It was the tightest pajamas ever. On his stilts, you were always the height of his balls. It was quite intimidating.”