It’s one of the most iconic dresses ever worn by a member of the royal family, and now Princess Diana’s so-called revenge dress is up for auction at Sotheby’s.

The famous black dress tells one hell of a story, worn on June 29, 1994, the same night her husband told the world he’d been having an affair.

WATCH THE VIDEO ABOVE: Princess Diana’s revenge dress up for auction

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“Did you try to be faithful and honourable to your wife when you took on the vow of marriage?” the-then Prince Charles was asked in an interview with the BBC’s Jonathan Dimbleby.

“Yes, until it became irretrievably broken down,” he replied.

7NEWS has been given rare access to the garment, more than 30 years after Diana stole the spotlight in the famous dress.

“It says to the world that she was ready to stand up and fight for herself,” Sotheby’s head of fashion Morgane Halimi said.

“It’s so much more detailed than any picture would show.”

The one-of-a-kind item is attracting interest from museums, institutions and private collectors.

First auctioned two months before she died, the revenge dress has been privately owned until now, and will go up for sale in New York City in December.

It was one of the most recognisable fashion statements in modern history, and now, more than 30 years later, the revenge dress is expected to go for at least $400,000.

Diana’s famous black sheep jumper sold for more than $1.5 million in 2023.

“We don’t know where it’s going to land,” Halimi said.