The Bride Wars actress ensured her sunkissed pins were on full display for the glitzy occasion, teetering along in a pair of pointed white Louboutins.
Gorgeous Kate opted for a silky canary yellow blouse by Emilio Pucci complete with a deep plunging neckline.
The blonde bombshell made sure her modesty was covered at all times by wearing a white vest underneath, accessorising with a long necklace.
She tucked her blouse into a teeny tiny white miniskirt while toting a sparkly silver rectangular clutch.
To complete her look, Kate - who is engaged to Muse frontman Matthew Bellamy - whipped her locks into a top-knot, adding a flick of liquid liner and clear lipgloss.
The starlet also bumped into actress Naomi Watts at the bash, who she starred alongside in the film Le Divorce back in 2003.
Naomi went for a more covered up look, cutting an elegant figure in a strapless black dress by Altuzarra with pink and red detailing across the bust.
She teamed her frock with simple Jimmy Choo heels and a statement bejewelled necklace, styling her tresses in a whimsical updo.
Other attendees at the star-studded event included Twilight star Ashley Greene, Glee actress Dianna Agron and brothers Nick and Joe Jonas.
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