Margaret Qualley Was Given Prosthetic Boobs to 'Endow Me with the Rack of a Lifetime' for The Substance

Margaret Qualley went all out to play her character in The Substance.

While speaking to The Sunday Times, Qualley — who plays Sue alongside Demi Moore's Elisabeth Sparkle in the film — recalled working with an "incredible" prosthetics team to get the right look for the movie.

Qualley, 29, explained how director Coralie Fargeat's “vision of Sue was '80s inspired, with butt and boobs, think Jessica Rabbit.”

“Unfortunately there is no magic boob potion, so we had to glue those on,” the actress told the outlet. “Coralie found an incredible prosthetic team to endow me with the rack of a lifetime, just not my lifetime.”

In the film, Moore's character is a celebrity who tries a black-market drug to create a younger version of herself. That new version of the character is played by Qualley.

The topic of aging in Hollywood and sexuality has been mentioned multiple times in interviews while the pair have been promoting the film, which had its North American premiere at the Toronto International Film Festival.

During her chat with The Sunday Times, Qualley spoke about a challenging scene where her character leads a sexy dance class.

“That specific kind of sexuality doesn’t lend itself to me," she admitted, telling the outlet that tears were involved when she first rehearsed the scene in question.

Per the Los Angeles Times, the prosthetics used in the movie were created by French makeup artist Pierre Olivier Persin. At one point in the film, special effects were used to create Monstro; a mashup of Moore and Qualley's characters.

“I was in there, with [Demi’s] face plastered onto my own body,” Qualley told the outlet.

After Moore, 61, admitted, “I don’t think we could have fit both of us in the suit," Qualley then insisted, “I wish you were in there with me!”

She added, “I was alone in that thing. I was running into things. It was a torture chamber. The amount of videos I have of me like, ‘I can’t do this anymore.’ It was eight days. I know that doesn’t seem like a lot.”

“We would just go until I had a panic attack. And the tempting thing is you want to peel it off, but of course you can’t do that, because you’ll bring your skin with you,” the Poor Things star continued.

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The Substance is in theaters on Sept. 20, 2024.