It has been 42 years since Princess Diana and then-Prince Charles (now Charles III) said “I do” at St. Paul’s Cathedral in London, England. Their wedding became the 20th century’s most-watched televised wedding, and it was etched in the collective memory of everyone who enjoyed the royal event on July 29, 1981. Undoubtedly, the princess stole the show, dressed in her magnificent wedding gown with puffed sleeves, adorned with 10,000 sequins, mother-of-pearl and a 25-foot train. That dress has gone down in history. Four decades after those nuptials, the gown’s designer, Elizabeth Emanuel, revealed one of the royal wedding’s best kept secrets: Lady Di had a spare dress ready to go, just in case.

Designers David and Elizabeth Emanuel made Diana the star of the show in a dress that perfectly represented the excesses of the 1980s and the majesty of royal weddings. But this historic image could have been very different. Queen Elizabeth II gave up an abandoned wing of Buckingham Palace to dedicate to crafting the gown, as that was the only place the designers had enough space to shape the endless train. But as with everything that happens in royal households, there is usually a plan B (and even a plan C). The bride and groom wanted to avoid any leaks about what is always a wedding’s best-kept secret, so they decided to commission another design. “The spare wedding gown was made just in case the secret of the real dress ever got out. Fortunately, it was never used,” the designer explained to Hello! magazine 42 years later.

This second gown was quite different from the first option. “The dress was made in pale ivory silk taffeta with embroidered scalloped details on the hem and sleeves. Tiny pearls were sewn on the bodice,” Emanuel noted. The sketch of the original design and some images that show the dressmaker working on that second dress were given to the British magazine. In the photos, one can see how some details of the original were retained in the second dress. That said, the latter was more discreet, with a V-neckline and a ruffle trim, three-quarter sleeves and a wide princess skirt.

Prince Charles and Princess Diana of Wales leaving St. Paul's Cathedral, July 29, 1981. Hulton Archive (Getty Images)

Emanuel does not know what happened to the dress after the wedding. “It was really just a back-up to the original and I don’t know where it went. It just disappeared,” the designer says now. That did not happen with the original wedding gown, which was exhibited at Kensington Palace two years ago and remains stored among the British royal family’s treasures.

Four decades ago, everyone in the media tried to get an exclusive of the soon-to-be dress of the century. Diana herself asked the designers to take every possible precaution against that: “She asked us to keep it very, very secret, which we did.” Still, the press wanted to know who was designing her wedding dress, and they had to announce it before the big day. The Emanuels spoke to their team working on the princess’s dress to avoid any leaks: “Our staff were wonderful and very loyal and didn’t talk to anybody. We had the dress stored every night in a metal cabinet guarded by two guards, Jim and Bert. So, there was somebody there 24 hours a day and we put shutters on all our windows, and we put false colour threads in the rubbish bins because people were going through our bins.”

Diana of Wales with designers David and Elizabeth Emanuel on August 6, 1986, at Kensington Palace. Tim Graham (Getty Images)

But the wedding dress was not Elizabeth and David’s only design for Prince Charles and Princess Diana’s wedding festivities. The duo made a dress for the pre-wedding ball held at Buckingham Palace. “Diana asked me to design a very sexy dress to shock everyone,” the dressmaker explained. Four decades later, we do not know what has become of that dress either, but we do know that it was a “shocking” pink, form-fitting frock.

Prince Charles and Princess Diana of Wales, waving from Buckingham Palace after their wedding on July 29, 1981. Express Newspapers (Getty Images)

At just 20 years old, Princess Diana became an icon and an inspiration for many (and as we approach the 26th anniversary of her death on August 31, she still is). For years, her outfits were renowned for their great taste, and she remains on everyone’s mind today. Many people fell in love with her dressed in her white bridal gown, while others did in 1994, when she wore her so-called “revenge dress,” the outfit she wore the same day her husband, Prince Charles, announced that he had cheated on her with Camilla Parker Bowles.

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