In “Anatomy of a Scene,” we ask directors to reveal the secrets that go into making key scenes in their movies. See new episodes in the series on Fridays. You can also watch our collection of more than 150 videos on YouTube and subscribe to our YouTube channel.

A miracle drug starts to create some side effects in this scene from “The Substance.”

Elisabeth Sparkle (Demi Moore) has been taking a black-market drug that has created a younger version of herself, Sue (Margaret Qualley). Her time must be divided between the younger and older versions on a strict schedule, but in this sequence, Elisabeth finds out what happens if she doesn’t respect the balance of that time.

She wakes up after Sue’s wild evening to a disheveled apartment and one aged appendage, the result of Sue taking more fluid from Elisabeth’s body to buy more time in her young body. Elisabeth notices that one of her fingers now looks dramatically older than the others.

As she runs to the sink to try to wash the age away, the pace become faster and closer. Narrating the scene, the director Coralie Fargeat said, “The idea was all those close-ups that go more and more macro on the finger is to project Elisabeth’s fears and Elisabeth’s thoughts about what’s happening to her.”

As Elisabeth calls the Substance company to discuss her “alteration,” she is taunted by a giant billboard out her window that shows her younger self. Fargeat said that she included a shot from above on Elisabeth to “film her discomfort, the fact that she’s now threatened.” This point of view is almost “a face-off with her double, and above her as if she was tiny and oppressed by the situation.”

Read the “Substance” review.

Sign up for the Movies Update newsletter and get a roundup of reviews, news, Critics’ Picks and more.