The Mandalorian and The Book of Boba Fett made use of highly advanced technology in order to bring Luke Skywalker back to our screens, with a combination of de-ageing VFX, Deepfake, and Respeecher used to achieve that effect. The latter is actually a voice synthesizer that made it so Mark Hamill sounded as he did when the original Star Wars trilogy was filmed.
After all, voices change over the years, and in Hamill's case, he's now 70 years old. What this means is that the voice we heard in The Book of Boba Fett was, essentially, not real.
It's pretty mind-blowing, and when Inverse (via SFFGazette.com) caught up with Respeecher founder Alex Serdiu, they got some insights into how the process works. "In general, there are two approaches to synthesize a voice," he explains. "The one the most well known and would be text to speech like an Alexa speaker or Siri. What we do obviously isn’t like that."
"We can’t synthesize a performance. That means that someone should be saying the lines that are needed to be converted into a target voice." So, Hamill - or perhaps even another actor - delivers a basic vocal performance and then Respeecher changes that so it sounds like a young Luke Skywalker. In this case, countless hours of audio from the movies and even audiobooks were used in order to teach their A.I. how to talk like the character.
With Respeecher also credited for Obi-Wan Kenobi (starting with the third episode), the site wondered whether their technology has also been used for Darth Vader. James Earl Jones certainly sounds a lot more youthful in the show than he did in 2016's Rogue One: A Star Wars Story, and at 91, we don't know how active he is as a performer these days.
"I can’t say yes or no on James Earl Jones," Serdiuk quickly responded, adding there are "lots of secrets still with Obi-Wan Kenobi. But we were uploading data packets [for Obi-Wan Kenobi] to Skywalker Sound when the invasion [of Ukraine] began."
It sounds like they did work on the show, but are currently unable to comment. Jones may well have recorded the lines so his performance shines through, though we can't help but wonder whether that might have been Hayden Christensen's doing with his voice before it was swapped out for this A.I. version of Jones/Vader. Hopefully, a future "Gallery" special will clear things up.
For now, you can read more about Respeecher by clicking here.