The actress who is known for her love of little black dresses and checkered prints went all out in the stunning sheer number which boasted hundreds of embroidered blooms, crystals and lashings of glitter from the neckline right down to the hem.
Rachel took a fashion risk in the almost see-through dress that flashed her bra and knickers but as always, the gorgeous blonde managed to pull the entire look off rather effortlessly.
And it wasn't just her dress that had us swooning as Rach's super-feminine hair and make-up had our beauty buzzers going off, too!
Proving that nudes are so overdone, the Hollywood star went all girly on us with a carnation pink lip against a simple veil of foundation and just a touch of peachy blush which sat prettily on the apples of her cheeks.
When it came to her tresses, Rachel switched it up and slicked her bangs to one side, fixing the rest of her lengths to the nape of her neck for touch of ladylike chic and to let the dress do most of the talking.
Rachel dazzled the paps who queued up to catch a glimpse of her looking deliciously stylish as she shared a laugh with dapper looking on-screen co-stars Brian d'Arcy James and Mark Ruffalo before taking her seat inside the venue.
What we'd do for a twirl in that frock...
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