WENN / Rex USA 1 / 11
WENN / Rex USA 1 / 11

Duchess Kate may not hail from Hollywood, but she can work a red carpet with the best of 'em. Attending the London premiere of "Mandela: Long Walk to Freedom" with Prince William on Dec. 5, the Duchess of Cambridge looked positively ravishing.

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Prince George's parents arrived at Leicester Square at exactly 7:15 p.m., and took their time making their way into Odeon Leicester Square Cinema. Kate, 31, was radiant (and, of course, slim) in a slinky, cream-colored Roland Mouret gown -- the "Lombard" -- which she accessorized with a black clutch, black heels, and a sparkling statement necklace from Zara. (It retails for just 20 pounds!) Her hair, now a richer, darker brown, was pulled back into a low ponytail.

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The Duchess has actually worn the Lombard before -- to a dinner at Claridges in 2012. In January, designer Mouret spoke about the gown with the Sunday Telegraph.

"I think it was quite fantastic that there was a split up the front," he said. "That picture of a woman when you catch a little of the leg, that's what you want to see. It's that notion of privacy. ... It's something that should be for her husband and she just shows a glimpse of it."

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Speaking of which, the Duke looked pretty dapper himself at the premiere in a black tux and black velvet loafers. He and his wife of two years were all smiles -- despite the rain! -- as they mingled with fellow moviegoers, including Zindzi Mandela, the daughter of former South African president Nelson Mandela, on whom the film is based.

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Prior to the screening, the Duchess took a few moments to chat with actress Naomie Harris, who plays Mandela's wife, Winnie Madikizela-Mandela.

The premiere was this year's Royal Film Performance, an annual fundraising event for the Cinema and Television Benevolent Fund (CTBF), a U.K. charity for people who work in the entertainment industry. Last year's movie of choice was "The Hobbit: An Unexpected Journey." Prince William attended that screening alone, as his then-pregnant wife was suffering extreme morning sickness at the time.

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"We are most grateful to the royal family for their continued support since the very first Royal Film Performance event back in 1946," CTBF president Barry Jenkins told reporters. "The funds raised from this event make a huge difference to the lives of industry colleagues and their families in times of great need."


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