For Us Weekly's special, Disney/Lucasfilm–sanctioned Rogue One: A Star Wars Story collector’s edition issue (on newsstands now, or order online), we got the cast and crew to reveal some juicy details regarding the movie’s plot, characters, what went on behind the scenes and more. Here, a handful of fun facts that'll have fans buzzing ahead of the film’s highly anticipated December 16 release.

1. Sigourney Weaver was an inspiration for Jyn Erso, Rogue One’s maverick protagonist.

“I worked with Sigourney last year on a film called A Monster Calls,” star Felicity Jones (Jyn Erso) tells Us. “She is an absolute inspiration — someone who’s always had her own way of doing things and who has always played rich, fascinating female characters." Indeed, Weaver's most famous role of all, Ripley from the Alien series, “was definitely a reference for Jyn,” says the best actress Oscar nominee (for 2014's The Theory of Everything).

2. Rogue One marks the return of Darth Vader.

The moment he first came into contact with the infamous Sith Lord will forever be etched in Diego Luna’s brain. “I was taken to a set that was an Imperial bay, and I hear [heavy breathing]," the actor, who plays the Rebellion’s Captain Cassian Andor, tells Us. “I’m like, 'This is real!’” Adds producer Kathleen Kennedy: “Vader will be in the movie sparingly. But at a key, strategic moment, he’s going to loom large.”

3. Forest Whitaker’s character, Saw Gerrera, is an old pal of Vader’s.

The two fought side by side during the Clone Wars — back when the helmet-headed baddie went by the name Anakin Skywalker. While Saw's fellow Rebels question whether he’s a terrorist or a revolutionary, Whitaker defines him as a “freedom fighter," saying: “Saw believes his world is about to be destroyed, and the losses he may need to inflict to stop it are much smaller than what’s about to happen to the universe."

4. The London Underground is a stand-in for the Imperials’ high-tech command center.

“Initially, everyone laughed” at Gareth Edwards’ idea to film at a “futuristic” station, the Rogue One director himself tells Us. "Then they went, 'Hang on, that could work!'" After shooting, as commuters streamed onto the train platform, “you wanted to point to the guy next to you and say, ‘He’s a Stormtrooper! We just shot Star Wars!’”

5. George Lucas was in the house.

As the film’s production designer, Doug Chiang, tells Us, the father of all things Star Wars "did visit Rogue One when we were in the middle of production. It was great to just show George the designs and what we wanted to do, especially since this film is so close to Episode IV [in terms of the Star Wars timeline]." FYI: Rogue One takes place immediately before the very first Star Wars release, 1977's Episode IV: A New Hope.

6. Not just Stormtroopers — the Empire now has Death Troopers!

Standing at 6-foot-5, these formidable, all-black-clad, Navy SEAL–like soldiers protect the Empire’s military director, Orson Krennic. “I’m proud they’re my guard!” Ben Mendelsohn tells Us, adding that he also liked swanning around the set in his regal, caped costumes. “Krennic is in the upper echelons of the Imperium,” thus “his much better dress sense” than the ragtag group of Rebels he’s trying to eradicate.

Us Weekly's Rogue One: A Star Wars Story collector's edition issue is available on newsstands now, or can be ordered online. The film hits theaters everywhere Friday, December 16. 

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