The Superman Returns actress looked the picture of elegance in a long black gown by Christopher Kane, featuring glimmering embellishment around the neck and waist.
Gorgeous Kate - who arrived with new hubby Michael Polish - let her fancy frock do all the talking by pairing with simple satin courts and a boxy clutch.
She highlighted her porcelain complexion with a touch of pink blusher, adding just-bitten rosy lips and pared-back peepers.
But while we loved Kate's glamorous get-up, we couldn't help but notice her bizarre barnet blunder.
The starlet added thickness to her locks with a warm, honey coloured hair piece, which didn't quite match her own ashy blonde locks. Oops.
She plaited the lengths before securing along the back of her head, leaving her black hair elastic visible. Hmmm.
We're not at all keen on this hairdo - bring back the tousled tresses, Kate!
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