The pretty brunette stunned in a midnight blue frock as she stepped out at a screening of her television series The Vampire Diaries, in which she plays leading lady Elena Gilbert.
Proving you don't have to flash the flesh to look incredible, Nina opted for a studded blue dress by Michael Kors which fell well below the knee.
But her frock did feature a cheeky peek-a-boo cut-out detail across the chest, revealing a glimpse of her décolletage.
The actress highlighted her slender silhouette by cinching her waist with a black skinny belt while showing off a ginormous sparkling cocktail ring on one finger.
Nina also toted a dazzling silver clutch by Edie Parker, completing her look with black strappy sandals.
But while we liked Nina's ladylike frock, we loved her hair and make-up!
Her tumbling locks were swept back into a messy half-up, half-down 'do with a schoolgirl ribbon securing it all in place. Cute!
She got things right on the beauty front too, decorating her deep chocolate peepers with smoky brown eyeshadow before adding a pop of coral to her pout.
And it was really only fair Nina looked drop-dead gorgeous for the event, seeing as her ex-boyfriend (and fellow Vampires Diaries castmate) Ian Somerhalder was in attendance too.
Nina and Ian dated off screen for three years, before calling time on their romance in May 2013.
What do you think of Nina's dress? Let us know by commenting below as the best comment across the site each week wins £50!
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