Demi Moore is unrecognizable in shocking photos from The Substance

Demi Moore gives fans a Halloween surprise.

On Thursday, October 31, Moore, 61, shared five behind-the-scenes photos from the set of her horror shocker The substance on Instagram as soon as the film is released on Mubi. The photos show Moore completely transformed, wearing glasses over heavy makeup and prosthetics designed to make her look like a very old woman, with minimal hair and flabby body parts.

“I've been keeping these gems from @trythesubstance and today seems like the right day to share them,” Moore wrote in the caption to her post. “Happy Halloween from Elisabeth Sparkle 🧪.”

In The substanceMoore plays Hollywood star Elisabeth Sparkle, who is fired from her long-time gig as host of an aerobics television series on her 50th birthday. Elisabeth is then introduced to a black market drug called The Substance, essentially creating 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 aggressively changes over time.

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Moore's contribution gives The substance Fans get a full look 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 achievement. “I love you 😂,” wrote Emma Heming Willis, who is married to Moore's ex-husband Bruce Willis, while Michelle Pfeiffer simply left three “🙌🙌🙌” emojis in her own comment.

“So good!!! You were amazing in that movie!!” Barbara Crampton added.

Moore and Qualley's film also stars Dennis Quaid, who plays the sleazy TV broadcaster responsible for Elisabeth Sparkle's aerobics show. The film was written and directed by French filmmaker Coralie Fargeat. It made headlines recently The Hollywood Reporter reported on October 21 that the film was submitted to the Golden Globe Awards in the Comedy and Musical category.

The substance is now in cinemas and streaming on Mubi.