The 73-year-old actress shared her transformation ahead of the awards on Sunday,Ã‚Â from bare-faced to red carpet ready, with herÃ‚Â 545,000 Instagram followers.
Mirren also shared her Ã¢â‚¬Å“afterÃ¢â‚¬Â look, dressed in aÃ‚Â Schiaparelli Haute Couture gown complete with Harry Winston diamonds.
Fans praised her for her honest transformation pictures.
One wrote: Ã¢â‚¬Å“You know, itÃ¢â‚¬â„¢s hard for people to understand that celebrities donÃ¢â‚¬â„¢t roll out of bed looking perfectly fabulous. (At least it is for me). You are beautiful before, and so glamorous after! YouÃ¢â‚¬â„¢re an inspiration and favorite of mine.Ã¢â‚¬Â [sic]
Another added: Ã¢â‚¬Å“You are beautiful with makeup, but without it you are a goddess!Ã¢â‚¬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, Ã¢â‚¬ËœBridesmaidsÃ¢â‚¬â„¢ actress Melissa McCarthy took a different approach, donning an Adidas tracksuit for the Vanity Fair Oscars after party.
Meanwhile, Ã¢â‚¬ËœGames of ThronesÃ¢â‚¬â„¢ star Jason Momoa dressed his pink velvet tuxedo down with the help of a matching scrunchie worn around his wrist.
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