Actor James Earl Jones will make his return to live-action movies after appearing on the animated series Star Wars Rebels. However, the fan favorite will not be seeing robust screen time, “He will be in the movie sparingly,” Lucasfilm president Kathleen Kennedy confirmed with Entertainment Weekly.
Jones will naturally be the voice Darth Vader once again in Rogue One: A Star Wars Story, allowing for a piece of authenticity from the original series to seep into this prequel.

Darth Vader was largely assumed, but only officially confirmed as appearing in Rogue One as of yesterday.
Despite rumors of Disney being severely unhappy with the production of the movie, and ordering expensive reshoots, Rogue One: A Star Wars Story is still slated to hit theaters December 16, 2016.