The actress, who is also known for her roles in Suffragettes and new Netflix movie The Dig, admitted that the review, written by a film critic in Variety, had "stuck with her".
She told the New York Times recently: "It made me concerned that in such a big publication, an actress' appearance could be criticized and that could be accepted as completely reasonable criticism."
WATCH: Carey Mulligan stars in upcoming new film Promising Young Woman
The Great Gatsby star added: "It stuck with me, because I think it's these kind of everyday moments that add up — that mean that we start to edit the way that women appear on screen and we want them to look a certain way."
The review in the online publication questioned whether Carey was the right choice for the role as Cassie, a woman whose life is derailed at university after being sexually assaulted, and added that fellow actress and the film's producer Margot Robbie, might have been a better choice.
The review read: "[Carey] seems a bit of an odd choice as this admittedly many-layered apparent femme fatale. Margot Robbie is a producer here, and one can (perhaps too easily) imagine the role might once have been intended for her."
Carey Mulligan as Cassie in Promising Young Woman
Meanwhile, the film has already proved a hit with film critics in general after premiering at the Sundance Film Festival in January 2020.
The synopsis reads: "Nothing in Cassie's life is what it appears to be - she's wickedly smart, tantalisingly cunning, and she's living a secret double life by night. Now, an unexpected encounter is about to give Cassie a chance to right the wrongs from the past."
Appearing on the Graham Norton Show recently, Carey said of the film: "It is the best script I had read. It is amazing and it's so many things – romantic comedy, thriller, revenge road movie. It's really hard to describe. It's so good to be in a film that is so dark, but fun at the same time."
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