Kate Middleton’s Semi-Sheer Dress Is the Best Holiday Party Outfit Inspiration

Kate Middleton just put her own spin on the black tie affair dress code, stepping out in a lace black Alexander McQueen gown for the annual Royal Variety Performance alongside Prince William.

The Duchess of Cambridge arrived at the event wearing the semi-sheer slinky gown with black heeled pumps, a black clutch, and a pair of dangly hoop earrings. Alexander McQueen is, of course, a favorite of Middleton's — who can forget her wedding gown from the house, or the floral evening dress she's remixed for multiple black tie events? It's even her go-to for wedding guest attire.

<p>John Phillips/Getty Images</p>

John Phillips/Getty Images

The Royal Variety Performance is an annual event supporting the Royal Variety Charity, of which the Queen is patron. The funds raised from the show help entertainers throughout the U.K. who need help and assistance as a result of old age, ill-health or hard times.

Inside the event, Kate and William met with well-wishers and performers, including the cast of Mary Poppins.

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Though the event usually includes an appearance from members of the royal family, the Duke and Duchess of Cambridge aren't always the ones who attend. Last year, Prince Harry and Meghan Markle made an appearance on behalf of the royals.