How Demi Moore and Margaret Qualley Physically Prepared for ‘The Substance’

Demi Moore and Margaret Qualley’s preparation for The Substance was as intense as their performances.

In the Coralie Fargeat-directed film, Moore, 62, played Elizabeth Sparkle, a fading Hollywood star and recently fired aerobics show personality. After Elizabeth takes “the substance,” Sue, a younger version of herself (played by Qualley, 30), comes out of her spine and becomes the industry’s latest ingenue. Sue takes Elizabeth’s spot on the fitness show, and the fame and desire to maintain her youth begins to consume both of them.

The Substance is a bloody, brutal and emotional exploration of the relationship between aging, stardom and womanhood, and despite its niche body horror genre, it has garnered mass acclaim throughout awards season. The film is nominated for five categories at the 2025 Academy Awards, including Best Actress for Moore and Best Picture. 

Moore’s nomination comes more than 40 years into her acting career, and she is considered a favorite to win in her category due to her wins at the Critics Choice, SAG and Golden Globe awards. Considering her full commitment to the role, it’s a well-deserved nod. 

In an interview with the L.A. Times, Moore alluded to being pushed to her limits with the role, revealing that on her first week off, she got shingles.

“And I then lost, like, 20 pounds,” she said.

The film called for full-frontal nudity for both stars, as Elisabeth studies herself in the mirror before taking the Substance, and then Sue considers her “new” body upon emerging from Elisabeth’s spine. But as Moore said, worrying about how she looked naked was hardly the point when it came to the film.

“Part of what was attractive is I knew that this wasn’t about highlighting my [body] and being lit in my most attractive ways, that in fact, it would be amplifying those things that you might see as flaws or that you don’t want somebody to see,” she told USA Today.

Later into the movie, as the Substance begins to backfire on the two, Moore had more prosthetics covering her body, requiring her to consider how she would move on-camera. 

“Some of that challenged my logical brain,” she told Screen Daily. “I have a humpback and I’m completely degraded physically, but I can run like a bat out of hell.”

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Meanwhile, Qualley has detailed her painstaking process to get ready for her iconic dance sequences. She told Entertainment Weekly that she had weekend rehearsals “for a long time” before shooting. On one of Qualley’s first days, Fargeat watched as the actress struggled to grasp the choreography.

“I was just like, ‘I’ll be right back, I got this!’ I just went to the bathroom and started sobbing and [then] was like, ‘Do you think we could do this one-on-one for a while?’ “ she recalled. “It was really outside my comfort zone. I’m not a natural.”

She added that “every goddamned day” on set pushed her to the brink physically and emotionally. The dance sequences — including her memorable workout to a cover of DJ Endor’s “Pump It Up!” — were “brutal,” according to Qualley.

In the USA Today interview, Moore says the film’s physical requirements were “something that really pushed us out of our respective comfort zones,” to which Qualley responded: “I mean, understatement of a lifetime.”