Director J.J. Abrams used extra footage of Fisher from 2015’s “The Force Awakens” and 2017’s “The Last Jedi” to help finish telling the character’s story, but had to enlist Lourd’s help when shooting a flashback scene to Leia's younger years. For followers of the “Star Wars” timeline, the scene takes place shortly after 1983's “Return of the Jedi” and shows Leia's Jedi brother, Luke, training her.
Mark Hamill reprised his role as Luke in the sequence, with de-aging technology utilized to help him look younger. Leia’s role, however, required a little more manipulation. Fisher passed away in 2016, so Lourd stepped in. Her face would later be swapped with a younger image of Fisher.
Lourd, who has her own role, Lieutenant Connix, in the sequel trilogy, stood in for seconds, but the “Star Wars” crew knew the magnitude of her work.
“Billie was playing her mother. It was a poignant thing, and something that nobody took lightly — that she was willing to stand in for her mom,” Patrick Tubach, the visual effects supervisor for ILM, a division of Lucasfilm, told Yahoo! Entertainment.
Tubach said Lourd was a natural fit for the job.
“It was an emotional thing for everybody to see her in that position," he said. "It felt great for us, too. If you’re going to have someone play (Fisher’s) part, it’s great that it’s (Lourd) because there are a lot of similarities between them that we were able to draw from. The real challenge was just making the Leia footage we had to work with fit in that scene.”
The scene gave fans a dose of nostalgia.
“The idea was to provide this great surprise where they take the helmets off, and you see Luke and Leia’s younger faces,” another visual effects supervisor, Roger Guyett, told Yahoo! Entertainment. “We scoured outtakes from the original movies, and we took some pieces and then had to try and figure out the technical aspect of putting that shot together.”