The stars of 'A Very British Scandal' on the bitter divorce that inspired it

It was a case of duke vs. duchess, Argyll vs. Argyll.

In the three-part Amazon Prime series “A Very British Scandal,” out April 22, Claire Foy and Paul Bettany act out the divorce between the Duke and Duchess of Argyll, which captivated the public in 1960s Britain.

"What makes it different from American scandals is that ours is steeped in the class system," Bettany told TODAY, referring to the fact that Margaret — who was an heiress — became an aristocrat through marriage.

Margaret Campbell became the third wife of Ian Douglas Campbell, 11th Duke of Argyll, in 1951. Over a decade later, after their marriage had gone sour, Ian broke into Margaret’s personal belongings and found photographs of Margaret naked with a still unidentified man, dubbed “the headless man" in the press for photos' below-the-neck angle.

The polaroids, as well as a list of 88 men whom the duke suspected Margaret had been with during their marriage, were submitted as evidence during the 1963 divorce trial. Ian petitioned for divorce on the grounds of Margaraet's alleged adultery.

“There’s been lots of books written about her,” Claire Foy told TODAY of her character, Margaret Whigham. “She wrote (a book) as well, which is about how to throw a good dinner party. No one wants to know about that. Everyone wants to know about the salacious elements of (her) divorce.”

Foy, while researching the role, read those books — and found them lacking in empathy for Margaret, which she hopes to bring to the show. “What I found out is that a lot of the books that were written about her were written by men, and had a lot of judgment about her and her sexuality and who she was," she said.

Judgment about her sexuality was something Margaret experienced during her lifetime. Famously, the judge presiding over the duke and duchess's divorce case wrote a 64,000 word judgement describing Margaret as a “a completely promiscuous woman" who was "wholly immoral" and had a "debased sexual appetite." He called her “a highly-sexed woman who had ceased to be satisfied with normal relations."

Speaking to TODAY, Foy laid out the basic “facts” of Margaret, which the judge did not pick up on in his statement.

“The facts about her really were that she was very entitled, privileged, and she came from a background where she got whatever she wanted from the men in her life — then married a man who refused to give her anything,” Foy said.

Of course, there are a few more facts about Margaret where those came from.

The only child of Helen Mann Hannay and George Hay Whigham, a Scottish businessman and millionaire, Margaret was born in 1912. After a childhood in the U.S, Margaret returned to England in her teens — a celebrity and heiress. “She was described as the greatest debutant as all time,” Charles Castle writes in “The Duchess Who Dared.”

By the age of 19, Margaret had been linked to a number of notable men: Prince Aly Khan; the Earl of Warwick; Max Aitkin, the son of a newspaper magnate; and aviator Glen Kidston. At 15, Margaret met future film star David Niven on the Isle of Wight, and became pregnant. She had an abortion, which was illegal at the time.

In 1933, when she was 20, she married her first husband, American millionaire Charles Sweeney. The had two children together, but Margaret also suffered eight miscarriages and a stillbirth during their 16 years of marriage. They divorced in 1947.

Margaret met Ian Campbell — who chief of the clan Campbell, Hereditary Master of the Royal Household in Scotland — on a train going from Paris to London. Ian had inherited Inveraray Castle in 1949, and that’s where they moved after they got married in 1951. Margaret was his third wife.

Their marriage, as "A Very British Scandal" shows, was troubled from the beginning. Ian struggled with substance abuse and carried emotional wounds from his time as a prisoner of war in Germany during WWII. He also expected Margaret to use her family's money to help restore the castle. Allegedly, both parties had extramarital affairs.

The divorce came after five years of estrangement, and was notable for how it played out in the press. “It was supposed to be a divorce hearing. But it became a trial,” series creator Sarah Phelps told Vanity Fair of the 11-day court case.

“It was the first case of its kind in the U.K," Claire Foy said, of the public case. "Divorce proceedings were always very private. There were never women of means who could bring a divorce case against their husbands. It was normally the husbands who were divorcing their wives, and it was pretty open and shut. But because Margaret had the means to take it to the bitter end, she was never going to give it up."

This tenaciousness meant Margaret's reputation was smeared, as commentators tried to guess the identity of the "headless man" with her in the Polaroids. After denying she was in the photos, Margaret was eventually identified by her jewelry, including a ring and a necklace of three strands of pearls. The vilified aristocrat was given a nickname of her own: "The Blowjob Duchess."

In "A Very British Scandal" charts Margaret's reaction going from being a darling of the press, to being quite the opposite.

"She was an it-girl. She grew up being lauded in the press. The narrative that she had created in her mind of who she was so quickly turned. It was basically a witch hunt for her, and everything about her. They loved the salaciousness of it, and the idea of it: She was a sexually promiscuous woman, and how dare she divorce her husband? Who does she think she is?" Foy said.

Today, Margaret could be considered a victim of revenge porn. Her life was never the same after the judge granted Ian a divorce on the grounds of adultery. She was ordered to pay her husband's legal fees, an equivalent of over $1.4 million today. She died in 1993 at age 80, with her fortune depleted.

The duke, meanwhile, remarried four months after his divorce was finalized.

Foy, looking back, said she saw echoes of the show's depictions of misogyny, sexual shaming and power imbalances in today's world.

"I thought I'd be shooting it and looking back saying, 'How terrible it was, this woman has been treated this way.' I realize that nothing has changed," she said.