Star-Studded: The Best Parties This Week

Have you ever been to a party so fabulous it felt like a dream? Picture celebrities decked out in one-of-a-kind cocktail dresses, clinking glasses of champagne, and air-kissing friends all night. Topic of conversation? Their favorite looks from the super-hot fashion show at which they sat front row that morning.

Well, that's exactly what went down inside New York's fantastically exclusive Top of the Standard on Tuesday night. Hours after Valentino Creative Director Pierpaolo Piccioli (above, center) debuted his headline-making Resort 2018 collection (flip-flops? at Valentino?), friends of the Italian fashion house zipped past the velvet rope and straight up the elevator, where Piccioli was on hand to greet everyone from Olivia Palermo and her husband, Johannes Huebl, along with Helena Christensen, Nicky Hilton Rothschild, Patricia Field, and Harley Viera Newton behind the DJ Booth (all dressed in Valentino, by the way).

Surprise, surprise: Mary J. Blige hit the stage for a groovy performance that surely brought the house down.

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Later in the week, the Whitney Museum of American Art transformed to host its 2017 Studio Party. On hand? Soo Joo Park and Katie Holmes, who also spent her busy week making the rounds at the American Ballet Theater's Gala, a posh affair that welcomed Blake Lively and, naturally, ballerina Isabella Boylston.

Scroll down for the best parties of the week.