Over 15,000 guests watched as Marilyn Monroe serenaded President John F. Kennedy for his birthday on the podium at Madison Square Garden on May 19, 1962. Fast forward over four decades, and that same dress just went under the hammer at Julien’s Auction House in Los Angeles.

The skin-tight gown was custom-made by Hollywood costume designer Jean Louis in accordance to a sketch by Bob Mackie. Adorned with over 2,500 hand-stitched crystals, it created the mesmerizing illusion that Marilyn was nude under the Garden’s bright lights. It was also so form-fitting that Jean Louis was tasked with sewing Marilyn into it, moments before she walked on stage.

Tonight was one of the most important moments in our history as a company,” Darren Julien, president and CEO of Julien’s Auctions, said in a statement. “We were incredibly privileged to have had the opportunity to offer this amazing dress from the most legendary screen star of all time.

The winning bid broke the world record for the most expensive dress ever purchased at auction—and was $1.8 million more than Julien’s Auctions in Los Angeles estimated it would fetch. In fact, the iconic dress just sold for $4.8 million!