During the filming of Rogue One there was talk of a secret element to the first Star Wars spin off story that had not been revealed in any trailer or promo image. Fans of the saga poured over the minutiae of the production and began to piece together a few clues that ultimately led them to the truth.

In amongst all the talk of how much screen time Darth Vader would have in the new film, and if the new characters were related to any of the Skywalkers, there was a piece of the Rogue One puzzle waiting to delight the fans, and it points a new way forward for an emerging technology.

Obviously there are spoilers for Rogue One: A Star Wars Story here. See it first before reading on.

ABC’s Nightline were recently granted access to Industrial Light & Magic to talk with John Knoll and his team about the process of bringing a character such as Grand Moff Tarkin back to life. Peter Cushing died in 1994, and while there’s not much talk here of the ethics of using an actor’s image (other than to comment that it has happened before) the technical wizards choose their words carefully.

Guy Henry CG Tarkin Rogue OneThe behind the scenes footage seen in the video centres on the process of transforming the performance of actor Guy Henry into a convincing recreation of the character played by Cushing. The technical tests and set footage compound the impressive nature of what ILM have achieved. At times the finished product did dip its toes in the uncanny valley for some, but we’ve heard from a lot of people that they didn’t realise the character was CG in any way – that’s the holy grail Knoll and his team have talked of for a while now.

CG Princess Leia Rogue OneAlso mentioned is the late Carrie Fisher’s reaction to seeing a nineteen year-old version of herself in a scene at the close of the film which has taken on new poignancy following the sad events of recent weeks. Here’s the full video from ABC,