In fact, while the film is billed as a standalone story, it actually acts as a sort-of prequel to 1977's A New Hope.
During the opening scenes of the latter movie, rebel Princess Leia (Carrie Fisher) hides the stolen Death Star plans inside droid R2-D2, ahead of her own capture by the evil Empire.
Rogue One, in a nutshell, is the story of how these all-important plans came to be stolen in the first place.
The sequel to The Force Awakens, Rian Johnson's Star Wars Episode VIII - which will continue the adventures of Rey, Finn and Poe Dameron - won't be released until December 2017.
If you put all the existing Star Wars movie in chronological order, this is how Rogue One fits in:
Episode I - The Phantom Menace (1999)
Episode II - Attack of the Clones (2002)
Episode III - Revenge of the Sith (2005)
Rogue One: A Star Wars Story (2016)
Episode IV: A New Hope (1977)
Episode V - The Empire Strikes Back (1980)
Episode VI - Return of the Jedi (1983
Episode VII - The Force Awakens December 18, 2015
It's the first of three planned "Star Wars Anthology" standalones
The schedule for Disney's forthcoming Star Wars slate, including three Star Wars Anthology (or standalone) films, is as follows:
December 16 2016 (AKA later this week!): Rogue One A Star Wars Movie, directed by Gareth Edwards.
December 16 2017: Star Wars Episode VIII, directed by Rian Johnson.
May 25 2018: A standalone movie set years before the events of Star Wars: A New Hope, focusing on the young Han Solo, and starring Alden Ehrenreich as Han, Donald Glover as a young Lando Calrissian, and (in an undisclosed role) Game of Thrones's Emilia Clarke.
December 2019: Star Wars Episode IX, directed by Colin Trevorrow
2020: A third, unconfirmed standalone movie. Previously, it looked as if this movie would be focused on popular villain Boba Fett, but plans to make the film with director Josh Trank fell through. Some people have suggested that a Boba Fett movie may still be in the works, but others have speculated that an Obi Wan-themed film might be more likely.
Yes, Darth Vader is in it
In a move that makes sense, given that Rogue One is set just before the events of A New Hope, everyone's favourite scuba-masked villain will feature in the film...and has already been glimpsed, in all his evil, black-glad, Vader-ish glory, in some of the trailers.
He'll be voiced by James Earl Jones, who provided vocals for the character in the original trilogy.
Han Solo isn't in it, but keep an eye open for Leia and Grand Moff Tarkin
It's been reported that key figures from the original trilogy, including Princess Leia and villain Grand Moff Tarkin, will appear in Rogue One thanks to some impressive digital trickery.
The latter character, who was so memorably played by the late Peter Cushing in Star Wars Episode IV, was even spotted (albeit from behind) in one of the recent trailers.
And Gareth Edwards, the film's director, recently seemed to hint that a certain ear-muff-haired royal might make an appearance, tantalisingly refusing to confirm or deny the rumour.
The main character is Jyn Erso, played by Felicity Jones
In the film, Erso is handpicked by a group of rebels to join the mission to retrieve the Death Star blueprints.
A previous trailer, released in October, also confirmed that Erso's father Galen, played by Mads Mikkelsen, has a significant part to play in the movie's plot.
In a scene shown in the trailer, Jyn discovers that her father, captured by the Empire, is "critical to the development" of the Death Star.
The film also stars Diego Luna as rebel captain Cassian Andor, Donnie Yen as blind rebel Chirrut Imwe, Ben Mendelsohn as evil Director Orson Krennic (the man in charge of making sure the Death Star is ready in time), Jiang Wen as Baze Malbus, Forest Whitaker as veteran Saw Gerrera and Genevieve O'Reilly as rebel leader Mon Mothma, a character who was first introduced in 1983's Return of the Jedi.
Mothma was played by Caroline Blakiston in the final instalment of the original trilogy but, in a nice twist, O'Reilly was actually was cast in the role in the prequel Revenge of the Sith (but ended up getting her scenes cut from the final cinematic edit).
There won't be any Jedi in it
The trailer above also suggested that the rebel Chirrut Imwe, played by Donnie Yen, may have some ability to use the Force.
But the film's director, Gareth Edwards has previously indicated that Rogue One will be a Jedi free movie.
"[Rogue One] is set in an era where there are no Jedi, or they're all but extinct," he revealed at the Star Wars Celebration in Anaheim, California last year.
"It's about the fact that God's not coming to save us. We're on our own - and we have to do this ourselves and turn around. The absence of the Jedi is omnipresent - it hangs over the whole movie - and it comes down to a group of individuals that don't have magical powers but have to somehow bring hope to the galaxy."
But there is a new droid
Stand aside, BB-8: there's a new droid in town.
K-2SO, the formidable robot you may have spotted in the trailers, is voiced by Alan Tudyk.
The character, a former Imperial slave droid, was freed by rebel leader Cassian.
