Unexpectedly she comes out of it completely physically unscathed but after she breaks down on the examination table one of the doctors secretly slips her promotional material for The Substance which promises to make a better, younger, version of yourself.
In a tailspin, Elisabeth succumbs to temptation, orders and administers The Substance and gives rise, messily on the bathroom floor, to Sue (Margaret Qualley). The Substance did not overpromise and underdeliver: Sue is perfect. Now the two must 'timeshare' life seven days as one, seven days as the other. There are strict procedures to follow.
No good will come of this.
CW: full frontal nudity, body horror ago-go-go, mutation, objectification of women (but subverting that's the whole point)
Coralie Fargeat screams "we are not things" in your face from about 6" away for 141 minutes through the medium of addiction, soft porn and body horror.
Like Revenge this is er, not subtle and relies on visual metaphor right from the start. We see Elisabeth's star on the Hollywood walk of fame get installed then increasingly damaged and ignored. There is comparatively little dialogue, people talk mostly at Elisabeth or Sue and the most human interaction is with an old schoolmate. The Substance comes from a dead drop and instruction on its use from a voice on the phone that may as well not be human.
As it gets to the final act it's completely bonkers with geysers of blood but the best of it is in the middle with Elisabeth trying to "doll herself up" and live a life while the spectre of the perfect Sue looks down on her from billboards and alternately Sue resentful of all her wasted time inert while Elisabeth comfort eats and watches TV.
Smarter people than me have analysed the feminist themes more deeply than I can but to me it's also about having a different public/private self and the compromises you make in balancing them.
The two co-stars are excellent and have courage for fulfilling the contrasting roles completely.
10/10 no notes and an important bit of indie cinema, you need a strong stomach though. Should win major awards but mostly won't because it'll be categorised as horror.