Princess Diana
Princess Diana's had two wedding dresses when she wed Prince Charles. Pictured: Princess Diana wearing a Jasper Conran suit during a visit to a community centre in Brixton, October 1983. Getty Images/Princess Diana Archive

Princess Diana wasn’t aware that she had a second wedding dress waiting for her when she tied the knot to Prince Charles years ago.

According to People, David and Elizabeth Emmanuel, the designers of Princess Diana’s bridal gown, created an exact duplicate of her dress as a back up in case the original one was ruined or leaked to the public. The backup dress is currently displayed at Madame Tussauds.

“At the time we wanted to make absolutely sure that the dress was a surprise. We wanted to make sure that we had something there; it was for our own peace of mind, really. We didn’t try it on Diana. We never even discussed it,” David said.

In 2005, Elizabeth also talked about the dress and said that Princess Diana wouldn’t have liked the idea that she would have to try the second dress on. After all, the late princess was so busy with all the other aspects of her special day to Prince Charles.

But even though the secret wedding dress was a duplicate of Princess Diana’s original gown, it was much simpler than what she wore when she walked down the aisle. The second dress featured a deeper V neckline, shorter frilled sleeves, and a ball skirt with no lace hem.

And it was never really finished. “It was only three-quarters finished – we simply didn’t have time to make it in its entirety, so none of the embroidery or finishing touches were done,” Elizabeth said.

While speaking with Daily Mail, Elizabeth also revealed that the second dress was kept in their studio, but it just disappeared without a trace.

“I don’t know if we sold it or put it into storage. It was such a busy time. I’m sure it’ll turn up in a bag someday,” she said.

In 2005, a replica of Princess Diana’s gown was auctioned by Cooper Owen for $90,000.