Demi Moore Is Unrecognizable in Shocking Behind-the-Scenes Shots from The Substance

Demi Moore is giving fans a Halloween surprise.

On Thursday, Oct. 31, Moore, 61, shared five behind-the-scenes photos from the set of her horror shocker The Substance to Instagram as the movie arrives on Mubi. The photos show Moore totally transformed, wearing glasses over heavy makeup and prosthetics designed to make her resemble a very old woman, with minimal hair and saggy body parts.

"Been holding onto these gems from @trythesubstance and today feels like an appropriate day to share them," Moore wrote in the caption to her post. "Happy Halloween from Elisabeth Sparkle 🧪."

In The Substance, Moore portrays Hollywood star Elisabeth Sparkle, who is fired from her long-running gig as the host of an aerobics television series on her 50th birthday. Elisabeth is then introduced to a black market drug known as The Substance, which essentially creates a younger version of herself (portrayed by Margaret Qualley).

The film ultimately follows the conflict that arises between Elisabeth and this other version of herself, known as Sue, as Sue finds her own fame in Los Angeles, and Elisabeth's body ages and morphs aggressively over time.

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Moore's post gives The Substance fans a full glimpse at the makeup and prosthetics (and blood) used for the role. Some of her famous friends chimed in with comments on her Instagram post praising the performance. "I love you 😂," Emma Heming Willis, who is married to Moore's ex-husband Bruce Willis, wrote, while Michelle Pfeiffer simply left three "🙌🙌🙌" emojis in her own comment.

"So good!!! You were fantastic in this film!!" Barbara Crampton added.

Moore and Qualley's movie also stars Dennis Quaid, who portrays the sleazy television network executive in charge of Elisabeth Sparkle's aerobics show. The film is written and directed by French filmmaker Coralie Fargeat. It made headlines recently after The Hollywood Reporter reported Oct. 21 that the movie was submitted to the Golden Globe Awards in the awards ceremony's comedy and musical category.

The Substance is in theaters and streaming on Mubi now.