The scenarios similar to Overlook Hotel, therefore to Kubrick, show a distorted and nightmarish reality for the protagonist Elizabeth Sparkle, the star system and Hollywood are dominated by the male chauvinist mentality, with advancing age women are forgotten and they are replaced and the same thing happens to Elizabeth.
Time is vital for the protagonist, the film begins on her birthday, her advancing age, but time also takes on a concept of waiting that devours Elizabeth in as after using the substance she has to wait a week to be able to take on the appearance of the other younger one, Sue.
So the obsession for beauty, for acclaim, Elizabeth fully lives the model of the star system managed by men mostly shown in a grotesque way, almost always framed with a wide angle to distort and therefore dilate their physiognomies by focusing on satire and caricatural moments.
The lenses of the cameras of the television studio where Elizabeth/Sue works point to perpetually obtain sexy shots, director Fargeat accentuates Sue's forms shown in the foreground through prosthetics and through editing and soundtrack obtains the effect of sensorial alteration, men dote on Sue while they now consider Elizabeth outdated.

< 0>Elizabeth will begin to feel more and more inadequate, the changes in photography are interesting as when Elizabeth is shown the tones are only dark and dark with many shots from behind while when the protagonist uses Sue's body the colors are more pop and bright.< br />Therefore the theme of the double, many shots recall the concept of division precisely because although in reality the conscience is always that of Elizabeth, progressively the protagonist will almost split the two personalities which will come into conflict with each other.

<0 >The references to Shining, Psycho but also Re-animator and Society are not random nor are they merely homages.
As written, the Overlook style scenarios and the wide angle serve to imprison Elizabeth in a distorted and disturbing situation with grotesque moments while as in Hitchcock's Psycho, the dynamic of the double is also central in The Substance, in Re-Animator the focus was on resurrection/immortality and control while in Fargeat's film the essence is that of youth, of perennial beauty because society, Hollywood requires this is not to be surpassed, therefore in Yuzna's Society the other bourgeoisie controlled everything, in The Substance it is Hollywood, the show business that imparts rules that suffocate women and replace them as if nothing had happened.

Elizabeth often crosses long corridors that through the wide angle seem infinite, everything is distorted, everything is a nightmare, she hates herself and no longer accepts her body.

Demi Moore's interpretation is masterful, the sequence where the now former actress (in the film Elizabeth was a successful actress) would like to go out to spend an evening but every time she looks at Sue's body and her portrait she is unable to accept herself ending up in oblivion it is handled very well and shows great skill of the actress.

The staging is excellent, the photography changes, the wide angle, the camera movements, when we move on to tighter editing everything has its meaning and purpose, Fargeat's technique is high.
The film also goes into body horror, the ending is grandiose, the bloodbath, the obsession with beauty and perennial success which creates a total distortion with the aforementioned quote, not an end in itself , to Society by Yuzna.
The subjective view via hand-held camera of Elizabeth is very interesting when, after using the substance, she looks in the mirror and sees Sue but with a tilted shot that recalls a sense of danger, the same subjective view takes place in the third act with a monstrous and well-executed directorial result.

The idea of ​​centering everything almost entirely between Elizabeth's apartment and the television studio is functional for the question of oblivion and mental imprisonment, the details of Elizabeth covering herself, lifting  her coat when she goes out so as not to be recognised, so as not to show herself because she is ashamed of herself are excellent and denote the character's psyche.
A film that through the excellent management of Fargeat strikes in several places, the satire and the grotesque for the chauvinism of show business, the obsession and oblivion of Elizabeth, the flamboyant pop and the sensorial alteration that Sue causes and obviously also the body horror.

<0 >Great, among the best horror films of the year, probably already of the decade and undoubtedly among the best films of the year.

I will watch it several times and perhaps following new viewings I will add others to this review themes and elements that I will find because the film has an immediate impact, clearly due to how it is shot, in the body horror and in the message it sends, cinematically it has many concepts within it for which with multiple viewings one will be able to understand the great work even better performed by Fargeat.