Rogue One: A Star Wars Story took place on planets brand new to the Star Wars canon, with one notable exception.
Tagging along with Imperial Director Orson Krennic, moviegoers were transported back to Mustafar, the lava world introduced in 2005’s Revenge of the Sith.
In the years following Anakin Skywalker’s emotionally-draining showdown with Obi-Wan Kenobi, Darth Vader erected a castle on the planet, which is where Krennic came to so he could complain to the Sith Lord about how unfairly he was being treated.
It was interesting to see that Vader had a place he could go where he could take a break from the Empire grind, and while Vader died a few years after the events of Rogue One, it’s possible we may see that castle again later down the line.