The sexy 65-year-old hit the red carpet in a smoldering scarlet one-shoulder Marchesa gown that featured a thigh-baring slit up the side, reports the Daily Mail.
She accessorized her ensemble with an elegant updo, a drapey red wrap, and a gold Marchesa clutch.
Mirren, who recently posed nude for New York magazine, was in the Floating City promoting her Dec. 10 release "The Tempest," in which she stars opposite Russell Brand and Djimon Hounsou as the Duchess of Milan Prospera, a female version of Shakespeare's sorcerer Prospero.
In director Julie Taymor's reinterpretation, the bewitching character is sent into exile simply because she is a woman in a male-dominated court.
"Women have been punished for being powerful for many centuries and I thought that was the remarkable thing about making Prospero into Prospera," the sultry sexagenarian, who is responsible for inspiring the grankini trend, told reporters.
"You can bring in that history of female struggle, and certainly in Shakespeare's day and for many centuries before and after, women of knowledge were punished for that knowledge... an educated woman is a dangerous thing."
As is one in a killer red dress!
In related news, read how Mirren is inspiring women over 60 to go glam.