The Substance
A fading celebrity decides to use a black market drug, a cell-replicating substance that temporarily creates a younger, better version of herself.
The premise centers on a drug that creates a younger, alternative version of the protagonist, with psychological dread and potential body-horror implications. Horror elements are meaningful and shape the experience, but the film also functions as a science-fiction/psychological drama about vanity and identity, so horror is not the sole or overwhelming driver.
Best for viewers looking for a scary and psychological horror movie.
Movies with a similar horror experience.