Jyn Erso takes down a half-dozen Stormtroopers single-handedly in the first clip from "Rogue One: A Star Wars Story."

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The footage debuted Wednesday on "The Tonight Show Starring Jimmy Fallon," where star Felicity Jones demonstrated some of her martial-arts training. "It was many hours of devotion and practice, and doing it over and over again," she explained. "And I'm wanting to kind of, you know, make Jyn a badass." Judging from the clip, which begins at about 2:09 on the video, Jones succeeded.

However, Fallon just happened to have on hand a baton like Jyn uses in "Rogue One," setting up a walkthrough of fight choreography similar to what we see in the clip. Needless to say, the talk-show host is no match for Jones.

Set prior to the events of 1977's "Star Wars," "Rogue One" follows a ragtag group of Rebels that unites for a seemingly possible mission: to steal the design plans for the Galactic Empire's planet-destroying super-weapon, the Death Star.

Directed by Gareth Edwards, the first "Star Wars" standalone film also stars Diego Luna, Ben Mendelsohn, Donnie Yen, Mads Mikkelsen, Alan Tudyk, Jiang Wen and Forest Whitaker. "Rogue One: A Star Wars Story" opens Dec. 15 in the United Kingdom and Dec. 16 in the United States.