This film defies being rated on a scale of 1 through 5 - it's truly almost impossible to do so. I want to rate this a 5 and I want to rate this a 3 at the same time. Both would be wrong though so I'll just settle in the middle. Aronofsky has given us many brainsick films in the past, but this is on a whole other level. Remember the batshit crazy climax of Requiem for a Dream? Multiply that by 50 and you get the batshit crazy climax of mother! - and that is a huge understatement.
I don't really want to talk too much about the film's plot or the finale as not much about the film is known to the public at this point. It's absolutely worth it to go into this film as blind as possible or maximum effectiveness. All I'll say is that the Rosemary's Baby influenced poster and marketing so far is a big curve ball - it has nothing to do with that film although Polanski horror elements are clearly an inspiration to Aronofsky here.
I do want to praise three specific elements of this film that worked the best for me: (1) The sound design was absolutely magnificent. There is no score to this film - not quite sure what Jóhann Jóhansson did here - but the sound design is eerie as hell and supremely memorable. (2) The production design is next level. The house in this film is basically the co-lead (you'll see what I mean when you watch it) and it evolves drastically over the course of the film (again, you'll see what I mean when you watch it). Excellent art direction that I haven't stopped thinking about all day. (3) The performance from Jennifer Lawrence is harrowing as she really gave herself to this film and to Aronofksy's vision, but the performance that stuck with me is the one from Michelle Pfeiffer. She really embodied her character and even though she's only in maybe the first 60% of the film, she left a deep impression on the rest of it as well. Her character is crucial to the film and she injected such mystery and gravity to the events that followed her exit.
Will soon watch this again and hopefully have more meaningful thoughts. It's hard to say too much right now when hardly anyone has seen the film yet, but believe me, there is a lot to be said about mother!