The 'One More Sleep' singer stunned in her figure-hugging number as she posed for photographers at the star-studded bash, while also flashing her intricate feather shoulder tattoo.
Leona's stand-out frock featured a small side slit and a sexy one-shoulder neckline, plus a metallic band which cinched in her waist.
With such a bright dress, the X Factor winner kept her accessories minimal, toting a black boxy clutch and wearing a chunky ring.
To finish her look Leona added a pair of pointed heels complete with chunky ankle cuffs and sparkly silver toes. Cute!
She styled her caramel locks in a bouncy blow-dry and opted for grey smoky eyes paired with a nude pout.
Other attendees at the event included fellow Brit lass Emeli Sandé, plus singer Kelis and former Destiny's Child star Michelle Williams.
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