When one hears the words "Princess Diana's Revenge Dress," most people probably immediately think of the image of the gorgeous off-the-shoulder black mini that Prince Charles wore the day she admitted to cheating on him on British television.

But apparently the dress may have originally been white, in which case the effect would have been so different.

"The story behind her 'revenge dress' is very interesting," royal fashion expert and author Claudia Joseph told Us Weekly.

"She went to Christina Stambourian's dress store with her brother Charlie Spencer, and he sat there while she tried on clothes.

Apparently, Diana wanted the same dress in white. But Christina said, 'No, I think black would look better,'" Joseph said.

"She groaned, 'Hmmm,' but Christina insisted, 'This would look great on you,' and in the end the princess chose black and attended the Serpentine Gallery that day in 1994."

Joseph also recalled that Princess Diana's style had evolved over the years.

"When she married (Charles), she was 20 years old. She told me she only had one long dress, one silk skirt, and one pair of shoes," Joseph explained.

"She obviously went shopping for the wedding, but gradually she needed more and more things. At that age, she had not yet found her own style."

She wore "sophisticated designer pieces" during her time as senior royalty, but had to re-create her sense of style again after the separation.

"I would see her in Chanel working suits," Joseph observed. She took a risk and wore a skirt that was a little shorter."

"When she was with Charles, she didn't wear heels because she didn't want to tower over him. But after the divorce, she could wear whatever she wanted"