Andrew James’s review published on Letterboxd:
Not really much new to say in terms of mental health and the lack of human stability, but putting it under the guise of an already well developed and known character and making it feel kind of "real" was a stroke of proverbial genius. It doesn't hurt that it's shot like a mother trucker too. So many great shots; should probably be up for best picture, editing, cinematography, original(?) screenplay and performance by an actor in a leading role.
Speaking of which, this is (literally) a monster performance from Phoenix. It's simply magnetic.
Top ten of the year for sure.