Sienna Miller Stuns in Sequined Thakoon Tuxedo at Met Gala

Sienna Miller takes the plunge with a deep neckline for the 2015 Met Gala held at the Metropolitan Museum of Art on Monday (May 4) in New York City.

The 33-year-old actress wore a custom Thakoon red chiffon fringe sequined tuxedo with a rope tassel belt.

PHOTOS: Check out the latest pics of Sienna Miller

The day before, Sienna was spotted grabbing a cup of coffee while spending time in the Big Apple ahead of the big fashion event.

This year’s Costume Institute Gala Benefit – celebrating the opening of the China: Through the Looking Glass exhibition – is co-chaired by Jennifer Lawrence, Chinese actress Gong Li, Vogue editor Anna Wintour, and others.

FYI: Sienna is wearing custom Jacob & Co earrings and carrying a Rauwolf clutch.