'Rogue One' revealed: What we just learned about the next 'Star Wars' film

LONDON -- On a dark and somber day for Europe, there was a small light of new hope.

At the official Star Wars Celebration convention at London's massive ExCel center Friday, Game of Thrones and Force Awakens star Gwendoline Christie took the stage in front of 4,000 people to introduce the cast and crew of Rogue One -- but not before calling for a moment of silence for the victims of Nice. That was followed by a rousing, spontaneous audience rendition of the French national anthem.

Here's what we learned in the hour that followed: the first standalone Star Wars movie, which hits theaters this December and deals with a nascent rebellion and its theft of the Death Star plans, looks pretty damn epic.

You can get a glimpse of just how epic in the behind-the-scenes sizzle reel unveiled at Celebration, below. We in the audience were also shown a supposedly "confidential" teaser, one that wasn't carried on the livestream; there appears to be some doubt as to when or if this teaser will be released publicly.

Suffice to say there was a fair amount of overlap with the sizzle reel:

Here's what else you need to know:

Darth Vader's role is awesome, but limited

Yes, the most famous villain in all of cinema is back. Vader is voiced once again by the man himself, James Earl Jones.

Rogue One director Gareth Edwards described himself as "having a nerdgasm" when Jones came to the studio to record the voice. In particular, the nerdgasm seems to have been triggered by hearing Jones say one word.

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The Celebration-only teaser featured a one-second image of Vader, in reflection, which seems a good rough guide to how much he's actually in the film.

Instead, the villainous focus is on Ben Mendelsohn's character, Director Orson Krennic. Mendelsohn made a stunning entrance through the crowd in imperial garb, flanked by all-black Death Troopers.

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Here's what the Rogue One exhibit at Celebration revealed about Krennic: He's basically the galaxy's most evil project manager.

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There's a new important planet in the galaxy, and it sounds amazing

The religion of the Jedi, and the history of the Force, is likely to be a focus of Star Wars Episode VIII, still untitled but coming in December 2017. After all, the one thing we knew about Luke Skywalker in The Force Awakens was that he'd decamped to the planet of the very first Jedi Temple.

But now it seems Rogue One will also have a hefty portion of Jedi mythology to offer. Some of it takes place on the planet Jedha, which Edwards described as the "Mecca" of the galaxy far, far away.

Original image has been replaced. Credit: Mashable

As with Mecca -- indeed, as with Jeddah, a real city pilgrims visit on the way to Mecca -- the planet Jedha is visited by those who seek to pay their respects to the ancient religion.

It is, however, being crushed by Imperial tyranny -- and that might have something to do with the mysterious red figures above, who look like a more boxy version of the Emperor's Royal Guards from Return of the Jedi.

The hero isn't like previous Star Wars heroes ...

It's become something of a Star Wars cliche: the hero with a mysterious past. Luke Skywalker wanted to learn about his absent, supposedly-dead father and follow in his Jedi footsteps. The Force-sensitive Rey in Force Awakens was such a mystery to herself, we still don't even know her last name.

That's evidently not the case with Jyn Erso (Felicity Jones), the hero of Rogue One:

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That said, there's still a parental mystery in the Erso family. Her father, Galen Erso (Mads Mikkelsen), is a scientist who "invented something beautiful that could have changed the galaxy."

Invented what? Your guess is as good as mine, but evidently it didn't work.

There are also flashbacks to Jyn's childhood in the movie -- as confirmed at the start of the audience-only teaser, when we see a young Jyn running through the grass of her home world.

... but there's still a droid for comic relief

We knew that Alan Tudyk, of Firefly fame, was playing a droid in the movie; he's the 7-ft tall one in the poster at the top. Now that droid has a name -- K-2SO -- and a backstory.

K-2 was an Imperial droid who was captured by the Rebels and reprogrammed. In the process of being reset, he developed his own quirky, sassy personality.

In a brief soundless clip shown during the panel, we see Jyn and K-2 on an unknown desert planet. They have a contentious exchange, at the end of which Jyn hands K-2 her pack to carry. K-2 looks down at the bag for a beat ... then drops it in the sand.

So there you have it. Rogue One has laughs, mysteries, mythology, and a small band of good people overcoming galactic villainy.

In other words, it may be exactly what the world needs after this rough year.