Prince William Hosts Emma Watson, Cate Blanchett at Star-Studded Windsor Castle Party: Pictures, Details!

Emma Watson
Emma Watson arrives for a dinner to celebrate the work of The Royal Marsden hosted by the Duke of Cambridge at Windsor Castle on May 13, 2014 in Windsor, England.  Chris Jackson/Getty Images

Impressive guest list, Prince William! On Tuesday, May 13, the Duke of Cambridge hosted A-listers including Emma Watson, Cate Blanchett, Kate Moss, Cara Delevingne, Helena Bonham Carter, and Benedict Cumberbatch at a star-studded gala dinner for The Royal Marsden Cancer Hospital, of which Prince William is the president.

With his wife, Kate Middleton, tending to Prince George at home, the Duke, 31, welcomed guests to the stately, gorgeous Windsor Castle in Windsor, England. There, he rubbed elbows with the stars and chatted with designer Ralph Lauren, who announced his plans to fund a new breast cancer center at the hospital.

"It's a wonderful thing you're backing," William told the fashion mogul. "It will be another great addition to the hospital." He also apologized for the Duchess' absence, quipping, "You probably would far rather you saw my wife."

prince william and kate
Doug Seeburg-Pool/Getty Images

In Lauren's honor, many celebrity guests were dressed head-to-toe in his designs. Harry Potter alum Watson, for example, wore a Ralph Lauren Collection silk jersey skirt and blouse, which she paired with a simple clutch and white belt.

Blanchett, meanwhile, was regal in a Ralph Lauren Collection ivory silk cady gown with an asymmetrical neckline. Statement earrings and an elegant updo completed the look.

Cate Blanchett
Chris Jackson/Getty Images

Model Moss opted for something a little sexier, showing up in a black gown with a thigh-high slit. And Bonham Carter turned heads in a dramatic, navy gown with layers of silk taffeta and organza.

Kate Moss
Chris Jackson/Getty Images

"The Duke and I met before, along with the Duchess, before they were married, when I was staying on Mustique," the Sweeney Todd actress said. "I got very drunk at one point and I was determined to ask him to be a godfather to my daughter. He quite wisely said no." She added, "I admire him. He has got the same grace as both his parents."

Sherlock star Cumberbatch expressed a similar fondness for the royal, saying, "He is just a stand-up guy." He noted, too, that the event was an important one for the hospital. "Hopefully tonight will raise awareness of the work of The Royal Marsden. That's what we're here for."

Indeed, the Duke made that clear in his speech before the dinner. "I am exceptionally proud to be president of The Royal Marsden, an incredible hospital and a world-class cancer center carrying out ground-breaking work, influencing the treatment of cancer both nationally and internationally," he said. He went on to highlight various philanthropic donations to the hospital before thanking Ralph Lauren for his generous contribution.

"I am enormously grateful to Ralph Lauren for his generosity, and to all of you who so kindly support the hospital," he said. "You should know that what you do saves lives and gives hope to thousands of people."

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