How The Book of Boba Fett Tricked Fans With Luke Skywalker's Voice

By Andrew Gilman Updated:
Luke Skywalker, Book of Boba Fett

It's been over a month since The Book of Boba Fett concluded its run on Disney+, but the show continues to have a major impact on Star Wars fans. In something of a shocking development, nearly the entirety of "Chapter 6" was devoted to following Grogu's time training at Luke Skywalker's Jedi Academy. The episode marked the first time either character had been seen since The Mandalorian Season 2's finale.

What happened aboard Moff Gideon's cruiser was the experience of a lifetime; countless videos on the internet feature grown adults weeping over the return of Luke in his prime. It was revealed shortly after the episode aired that Mark Hamill had reprised the role, with the assistance of a body double. Lucasfilm used deepfake technology to dial Hamill's face back to 1983, and the lines he read were re-dubbed with archival footage.

The Book of Boba Fett's process was significantly different. For one thing, Hamill wasn't involved in the shoot. He didn't do any ADR for the role either, despite his extensive background in voice work. Luke was played by a new body double for "Chapter 6," and his prominent screen time pushed ILM to generate his face with CGI - something that nearly every fan has noted is a remarkable improvement over the character's Mandalorian appearance.

"Chapter 6" was a magical experience, and it took a village to pull off the stunning return of the Jedi. In addition to the usual wizards at ILM, Lucasfilm brought in an outside company to do work on Luke - specifically for his voice. For the first time since the episode dropped, that organization has given insight into the Star Wars trickery behind crafting the iconic character's voice without Mark Hamill's services.

Luke's Voice in Book of Boba Fett Explained

Luke Skywalker, Boba Fett
Star Wars

In an interview with Variety, Respeecher co-founder and co-CEO Alex Serdiuk detailed the process behind creating Luke Skywalker's voice for The Book of Boba Fett. Serdiuk noted that the Ukrainian company was tasked with using old recordings of Mark Hamill's voice to generate Luke's lines, but things initially weren't up to standard:

"We heard recordings from 30 to 40 years ago, and those recordings were not good.”

To conquer the problem, the company tapped into archival recordings of Hamill's ADR sessions from the '80s, as well as recordings from video games and audiobooks. These quality sound clips were fed into the group's ReSpeecher app, which then generated new lines for Luke's "younger" appearance:

“Our technology applies a digital voice skin, digital vocal apparatus of that particular performance, and that gives content creators and moviemakers that full content over how it should sound and even inflections.”

After taking two weeks to "train a model," Serdiuk explained that data gathered would be fully developed into a voice, and Respeecher has many techniques at their disposal to make adjustments as clients deem necessary:

“If a director wants a voice sounding specific, we can tweak our models to meet those expectations.”

Respeecher began their relationship with Lucasfilm in 2019, and Serdiuk says the company took much away from working with Skywalker Sound:

“We learned so much from the sound engineers.” 

The technology Respeecher utilizes may be what some consider to be unnatural - and Serdiuk agrees that it could have a substantial impact on the future of synthesized speech:

“Our technology is very disruptive.”

A Pathway to Many Abilities

The behind-the-scenes process for bringing Star Wars projects to life has always been fascinating, with Lucasfilm constantly on the forefront of cutting-edge technology. What blew older fans' minds audibly and visually in 1977 was created completely from scratch by the company and its subsidiaries formed under George Lucas - ILM and Skywalker Sound.

Ensuing decades saw Lucasfilm continue to push technology forward. CGI was developed to great lengths in the Special Edition versions of the original trilogy films, and that continued into the early 2000s with the prequels. Attack of the Clones was the first movie to ever be shot on a digital camera, and blue screen work for the prequels was extensive. The newer films, for all their flaws and criticisms, have stellar, state-of-the-art visual effects. To pull off the MandoVerse, Jon Favreau coordinated with Lucasfilm to create The Volume set.

It's no surprise that a company willing to take so many risks to bring stories to life would make the jump into the archival recording realm with a group like Respeecher. Luke Skywalker is an integral part of Grogu's story; really, he's the only Jedi qualified to mentor the baby. Real-world drawbacks obviously exist, with Mark Hamill now much older than he was when first playing the character, but a CG Luke is, in many ways, more authentic to the character than a re-casting.

What Respeecher was able to accomplish is never short of remarkable. Some of their technology was used to generate the few lines Luke had in The Mandalorian, but his role in The Book of Boba Fett was far bigger than even the most imaginative fans could have expected. Syncing up the character's dialogue to the movements of another actor - whose own face was being replaced - takes extensive work.

There are certainly times when Luke's voice came across as awkward. At various points, the inflection that would normally be present in a line delivery by Mark Hamill was lacking, making the character feel slightly robotic. But it wasn't enough to break suspension of disbelief, and there were also moments when Luke sounded stunningly accurate. In many ways, "Chapter 6" was a time machine that took fans back to 1983.

It's likely that Luke Skywalker will appear again in the MandoVerse. While that may not come in The Mandalorian Season 3, it certainly could in Ahsoka. There's ample opportunity for the character to continue to be involved in the storyline - meaning Respeecher has more time to refine their technology and continue to improve upon the astonishing work that's already been done. In time, the difference between real and CG Luke will be indistinguishable.

All seven episodes of The Book of Boba Fett are available to stream on Disney+.

- About The Author: Andrew Gilman