The 73-year-old actress shared her transformation ahead of the awards on Sunday,Â from bare-faced to red carpet ready, with herÂ 545,000 Instagram followers.
Mirren also shared her â€œafterâ€ look, dressed in aÂ Schiaparelli Haute Couture gown complete with Harry Winston diamonds.
Fans praised her for her honest transformation pictures.
One wrote: â€œYou know, itâ€™s hard for people to understand that celebrities donâ€™t roll out of bed looking perfectly fabulous. (At least it is for me). You are beautiful before, and so glamorous after! Youâ€™re an inspiration and favorite of mine.â€ [sic]
Another added: â€œYou are beautiful with makeup, but without it you are a goddess!â€
Mirren also shared pictures of her having a ball at the ceremony, including a shot of her and Sarah Paulson in co-ordinating pink dresses.
While Mirren chose a glamorous look for the red carpet, â€˜Bridesmaidsâ€™ actress Melissa McCarthy took a different approach, donning an Adidas tracksuit for the Vanity Fair Oscars after party.
Meanwhile, â€˜Games of Thronesâ€™ star Jason Momoa dressed his pink velvet tuxedo down with the help of a matching scrunchie worn around his wrist.
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