The storyline is set in the time just preceding that of the first ever Star Wars movie (1977), Episode IV: A New Hope. It features Jyn Erso, the movie’s protagonist played by Felicity Jones, who “leads a group of unlikely heroes to steal the plans to the Death Star, the Empire’s “ultimate weapon of destruction,” as the caption bills it.

The two and a half minute video is sprinkled with the appropriate ratio of explosions, stormtroopers, blaster fire, and galactic orchestral gravitas. It opens with a flashback of Erso’s father, portrayed by Mads Mikkelsen, saying, “Whatever I do, I do it to protect you.”

Later, the viewer learns that the man is integral to the creation of “a super weapon.” (Hint: it’s the Death Star.)

Erso eventually escapes a prison cell and joins up with a ragtag team from the Rebel Alliance, the band of guerilla fighters resisting the rule of Emperor Palpatine, the galaxy’s ultimate baddie, and his cronies. Toward the end there’s a menacing cameo by Darth Vader, the franchise’s most recognizable villain.

The movie (first official trailer here) follows up on the blockbuster success of Disney’s franchise reboot with Star Wars: Episode VII – The Force Awakens last December. That film has banked more than $2 billion worldwide at the box office.

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Disney CEO Bob Iger has described Rogue One as “an experiment, of sorts,” because it is a standalone film featuring characters and a plot tangential to the traditional saga. Disney (DIS) bought Lucasfilm, the movie studio that owns the Star Wars franchise, for $4 billion in 2012.

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“We have hope,” Erso says at one point, clearly nodding to the title of the next film in the series’ internal chronology: A New Hope. “Rebellions are built on hope.”

As are gargantuan movie franchises. The film hits theaters December 16, 2016.