In the ongoing Star Wars chronology, Rogue One takes place just before the events depicted in the original 1977 Star Wars movie — A New Hope. To connect the two films, the new installment includes several characters who figure prominently in A New Hope — among them, Peter Cushing’s villainous Grand Moff Tarkin and a much younger Princess Leia played by Carrie Fisher.

As seen in this clip by ABC News, featuring an interview with ILM VFX supervisor and Chief Creative Officer John Knoll, there was a lot of technological movie magic to bring these characters back to the screen.