I was extremely hyped for that movie even though I'm not a big fan of Fargeat's debut film "Revenge". I liked her as a director, but not as a screenwriter. While that movie had interesting visual style, the screenplay was bad & stupid and the characters were uninteresting.
However she improved a lot from her last movie. "The Substance" looks amazing, the shots, the score, the editing, production design and even costumes are well thought out. The screenplay is also great (she actually won an award for Best Screenplay at Cannes for "The Substance"), the decisions that characters are making are understandable - they are results from characters' determination to achieve their goals.
I also loved Demi Moore's perfomance (it's worth mentioning that I wasn't considering her good actress at all, but after watching that movie, the first thought that came to my mind was that maybe she isn't a bad actress, she was just starring in bad movies), it's definitely highlight of her carrer. Margaret Qualley is great as always. Even Dennis Quaid, despite little screen time, gives fun and engaging perfomance.
Probably the most talked about part of that movie is gore and body horror elements. And, yeah, I must admit that this movie is pretty extreme and may be hard to watch for some viewers. Personally during those scenes I wasn't feeling disgusted or smth, cause I'm a big fan of disturbing cinema, so I'm used to that stuff, but I understand that it may be a hard journey for others. That proves how great make-up artist did their job (i would be happy seeing this movie nominated for an Oscar for "best make-up and hairstyling) and how sick and twisted Fargeat's imagination is.
Overall, I strongly recommend this movie. It may not be for everyone, but it's worth checking out for yourself and seeing it for yourself, cause even if u don't like it, u can't deny is isn't one of the most insane, extreme and interesting movie of this year (or even a decade).