There have been seven movies in the original Star Wars saga released from 1977-2015. The most recent installment, The Force Awakens has grossed $2 billion, a possible all time record for any movie. Episode eight is scheduled to be released in 2017, and a ninth and final installment is set to be released after that.
But, the Star Wars universe also includes at least 300 authorized novels set in that universe that are spin offs from the main story (excluding movie novelizations, children's books, short stories, reference books and role playing game spinoffs), and a made for TV animated movie together with a related six season animated television series (Clone Wars) that is a spin off from the main story setting forth the events between Episode III (the fourth released movie) and Episode IV (the first released movie from 1977).
Now, in that tradition of spin off stories, the franchise's new owner after George Lucas sold the franchise, Disney, will be releasing a live action spin off movie, Rogue One, on December 16, 2016. Rogue One tells the story of the theft of the plans to the Death Star that are ultimately used to mount the successful attack on the Death Star that takes place immediately before Episode IV and is alluded to and described summarily in dialog in this original Star Wars movie.
Considering that Star Wars is pretty much the best Space Opera ever written, and that the trailer for the new movie suggests that it fits seamlessly into the whole (albeit a bit darker; Disney refers to Rogue One as basically a "war movie"), more is better and this is great news.
Certainly, Rogue One is a much better contribution to an ongoing fictional universe than the critically deplored movie Batman v. Superman which has tanked at the box office, deservedly so despite the usual big motion picture studio big dollar production values.
Ultimately, a good story, which doesn't cost much more than a bad story, matters more than the extravagant means used to communicate that story. Rogue One sounds like a wonderful story to tell. Batman v. Superman, not so much.