Mary-Kate and Ashley Olsen Inside the 'Manus x Machina' Exhibit, 2016 Met Gala Afterparty Give Us Life

Mary-Kate and Ashley Olsen Inside the 'Manus x Machina' Exhibit, 2016 Met Gala Afterparty Give Us Life

Boom boom pow! Mary-Kate and Ashley Olsen had an amazing evening at the Metropolitan Museum of Art's Costume Institute Gala in NYC on Monday, May 2, and danced the night away at the official afterparty at the Boom Boom Room, where Us Weekly has exclusive details of the Row designers partying with their pals.

The girls, 29, first took to the red carpet Monday night in their signature oversized, monotone ensembles and accessorized their looks with jewels by Fred Leighton. Inside the storied Upper East Side institution, the Full House alums found themselves in Vogue's Manus x Machina experience: a videobooth directed by Gordon von Steiner that featured mesmerizing flashing lights and high-tech music.

"Ashley and Mary-Kate Olsen in the #ManusxMachina Experience," Vogue's official Instagram account shared, alongside a cool clip of the girls posing with their arms crossed and backs against opposite walls. The video begins with the famous siblings staring each other down. Then, the two slowly look over at the camera as it pans away and reveals the synchronized exposed lightbulbs that pulse with the music.

Ashley and Mary-Kate Olsen in the #ManusxMachina Experience. Directed by @gvsgvs. #MetGala

A video posted by Vogue (@voguemagazine) on

While the girls were typically stoic for their portrait session — unlike Madonna and Jaden and Willow Smith — they really let loose at the Met Gala's official afterparty at the Standard Hotel. 

An inside observer tells Us Weekly that the Olsen twins arrived right before Lady Gaga performed at 1:45 a.m. Ashley really wanted to get a good glimpse of Gaga, but was briefly stuck about 15 rows behind the stage. The insider says the designer was telling people how much she adores the "Just Dance" singer. 

Lucky for Ashley, a nice man helped her get to the front of the section, and the observer tells Us that the crowd parted ways just in time for her to enjoy Gaga's cover of "Burn this House Down." At one point, Gaga sang directly to Ashley, who smiled and danced along with a drink in her hand.

While most party attendees left the bash after Gaga's performance, the Olsens stayed and partied with their posse. Mary-Kate got wild at one point and jokingly spanked her pals. 

One song particularly got the girls amped and that was The Cardigans' "Lovefool." According to the observer, the twins and their friends formed a soul train and Mary-Kate joined the line. She did her best catwalk and sang the words, and even invited the bottle service girls — who were holding champagne bottles — to dance with her. Ashley, meanwhile, went crazy when DJ Questlove played "Word Up" a little while later.

"Both the Olsens were really cutting loose and having an amazing time with their friends," the observer tells Us.

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