'Rogue One: A Star Wars Story' Behind-the-Scenes Look Promises Badass Action and Plenty of Aliens

Lucasfilm Ltd

If you had any concerns about Rogue One: A Star Wars Story, this should more than assuage them.

This year's Star Wars Celebration kicked off in London on Friday and, amid rumors of reshoots and BTS turmoil, all eyes were on the galaxy far, far away's first anthology film. But the Rogue One team proved the movie is in good hands with a making-of featurette chock full of alien cameos and explosions, and it's safe to say this flick is going to put the "war" in Star Wars.

Stick around till the end for one seriously cool alien manning a seriously huge machine gun.

"The pressure's so high. Like, we're making a film that's right touching my favorite movie of all time," director Gareth Edwards (Godzilla) explains in the clip. "But if you're too respectful of it that you dare not do anything new or different or take a risk, then what are you bringing to the table?"

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That wasn't the only surprise for fans attending the Celebration. They were also the first to see the teaser poster for Rogue One -- a shot of the Death Star looming over a battle on the planet Scarif -- and watch the first full trailer for the film, which includes a cameo by Darth Vader!

Edwards, who was on hand to discuss the film, revealed he had a "nerdgasm" recording dialogue with the original voice behind the iconic villain, James Earl Jones.

Captain Phasma herself, Gwendoline Christie, was on hand to moderate the panel, which included Felicity Jones, Diego Luna, Ben Mendelsohn, Donnie Yen, Mads Mikkelsen, Forest Whitaker and more cast members. But this being Star Wars, everyone was sure not to let too many spoilers slip out.

Gareth did recall the day George Lucas visited him on set though, saying, "I challenge anyone to have a more surreal experience than showing a Star Wars film to George Lucas. He'd start to criticize something, then he'd make a joke and you'd realize he was just kidding. But we're all having heart attacks."

Rogue One: A Star Wars Story
hits theaters on Dec. 16.

Need a crash course on what Rogue One is all about? ET's resident Star Wars expert, Ashley Crossan, has you covered in the video below.