The Empire, personified by Director Orson Krennic (Ben Mendelson) and glimpses of Darth Vader, is diligently working on its new weapon — the Death Star.
For that, we have to wait for A New Hope… which already happened.
This is a prequel, that arrives decades after the original Star Wars.
The trailer covers two sides of the ongoing story.
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Rogue One: A Star Wars Story Trailer #2 (Official)