Diana, Charles, and Camilla: The Untold Story — New PEOPLE Special Edition Out Now!

“There were three of us in this marriage, so it was a bit crowded."

With those indelible words, spoken 25 years ago in a BBC television interview, Princess Diana shared with the world how it felt to be inside the most talked-about love triangle of the 20th century, between herself, her husband Prince Charles, and the then-married Camilla Parker-Bowles.

Now a new special edition of PEOPLE, Diana, Charles and Camilla: The Untold Story, takes an in-depth look back at a royal marriage that ended in scandal, the decades-long love story of the future King of England and the woman who will be his Queen Consort and the untimely death of the princess who had hoped to be Queen in people’s hearts.

Anwar Hussein/WireImage Newlyweds: Prince Charles and Princess Diana

Millions were enchanted by the 1981 fairy tale wedding of Charles and his young bride, Lady Diana Spencer, and then by the arrival of their sons, Princes William and Harry. But through that courtship and marriage, one of the Prince's ex-girlfriends, Camilla Parker Bowles, was by his side, first as a friend, then as a lover, which Charles had admitted in his own televised interview in 1994. Asked if he had been faithful to his wife, Charles at first said "yes," and then after a pause, told BBC journalist Jonathan Dimbleby, "Until it became irretrievably broken down, us both having tried."

PA Images via Getty Images Camilla Parker-Bowles and Lady Diana Spencer at a racetrack where Prince Charles was competing, 1980.

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At the time Camilla was married to Andrew Parker Bowles, who had once dated Charles's sister, Princess Anne, and was Commander of the Queen's Household Calvary; he had worked security at Charles and Diana's wedding, which Camilla also attended. Charles and Diana were separated, though not yet divorced, when she gave Panorama host Martin Bashir the headline-making "three of us in this marriage" interview. Why had Diana decided to speak out then? She told Bashir, "the perception that has been given of me for the last three years has been very confusing, turbulent and in some areas I'm sure many, many people doubt me."

Pool Photograph/Corbis/Corbis via Getty Images Princess Diana, speaking with the BBC's Martin Bashir, 1995

But by the official end to their marriage in 1996, Diana had grown so popular that her celebrity threatened to overshadow the rest of Britain’s royal family. With her concern for marginalized people, including AIDS patients, her elevated fashion sense and deft communication skills she emerged as a victor in the war of words fought by the estranged couple. The damage to her husband’s reputation, however, was longer-lasting. When Diana wondered aloud in the Bashir interview if Charles was fit for the “suffocating” role that awaited him as king, polls found that many Britons agreed with her. Then, when Diana died in a 1997 car accident, royal watchers felt the tragedy would doom any chance Charles would have for a happy ending with Camilla. "The specter of Diana is going to haunt him until the day he dies," declared author Brian Hoey at the time. "We've seen the end to any possibility of a marriage in the near future."

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But in the ensuing years, Charles not only restored his own reputation, he introduced the woman he had loved for so long on the world stage and convinced much of the British public that his former mistress could be their Queen. It helped that Camilla was embraced by his sons, and had the blessing of the Queen. Charles and Camilla, now Duchess of Cornwall, wed in 2005 in a private ceremony with far less pomp than the Diana-Charles nuptials, but that nonetheless inspired people with the idea that it is never too late in life to marry for love.

Rob Jefferies/Getty Images Prince Charles and wife Camilla, Duchess of Cornwall.

Filled with historic photos and People's unmatched royal reporting, Diana, Charles and Camilla: The Untold Story is available now on Amazon and wherever magazines are sold.