The Nashville actress turned heads as she attended the Environmental Media Awards in Los Angeles, where she picked up the Futures Award for her work with The Whaleman Foundation.
Her revealing lace frock featured a chic orange pencil skirt, which hugged her slender figure perfectly. Despite the strategically-placed criss-cross detailing, Hayden still flashed a hint of her nude bra in the sheer dress. Oops.
She added inches to her 5'2" frame with towering patent courts, sweeping her blonde locks into a tight topknot.
But the star of her outfit was her glimmering diamond engagement ring, which is reported to have cost an eye-popping $500,000.
The petite actress recently got engaged to boxer Wladimir Klitschko, and has since revealed she designed her show-stopping bling herself. Impressive!
While many accessorise their sparklers with a coloured mani, Hayden proved she's a low maintenance gal by keeping her talons bare.
She completed her look with bold brows and black eyeliner, adding a light coat of mascara and glossy lips.
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