The true story behind the most fascinating romance in The Crown season two.

The Crown season two may centre on the rocky marriage between The Queen and Prince Phillip, but there’s another relationship that steals the show.

Once again, Princess Margaret is involved.

After making the heartbreaking decision not to marry her first true love Captain Peter Townsend in season one Princess Margaret feels lost. She’s going out and drinking (even more) than she usually does, with the growing pressure to marry and settle down coming from every angle.

We see her meeting fashion photographer Antony Armstrong-Jones, or 'Tony', unlike any man she's ever met. That's exactly what attracts her to him. The latest season of The Crown charts their meeting, budding relationship and subsequent marriage, but how true to reality is it?

Quite. And in fact, their marriage was possibly even more colourful, sad and history-making than you see on screen.

While the Netflix series sees the pair meeting at a party in 1958, Armstrong-Jones' relationship with the Royal family began the year before when he took portraits of the Queen and family at Buckingham Palace.

However as an active member of high class society, it isn't impossible to imagine Princess Margaret asking her lady-in-waiting, Elizabeth Cavendish, to find her any man but one who "breeds horses, owns land, or knows my mother" as she does in the show.

But the scene in episode four in which the seeds of their attraction are planted, where he takes her photograph, isn't quite true to history.

LISTEN: The Binge chats to Vanessa Kirby about her role as Princess Margaret in The Crown. Post continues after audio...

He did take the picture which actress Vanessa Kirby recreates but not until 1967, after they were married, reports Vanity Fair.

Regardless, it was his total nonchalance - to her anyway - of her royal status that attracted her to him.

"With the utmost politeness, he made her change her clothes, her jewelry, and her pose as if she were any other sitter, at the same time chatting away with his mixture of jokes, gossip about mutual friends, and stories of the theatrical luminaries he had photographed," Anne De Courcey wrote in her biography of Lord Snowden, of which an extract was published in Vanity Fair in 2009, of the first time she posed for him.

“Margaret, accustomed to unquestioning deference, had never met anyone like him.”

Immediately deciding she wanted him in her social circle, the two soon developed a relationship which they had to conduct in secret.

She visited him in disguise at his studio and they were able to spend weekends together at "safe houses" of friends, including his very close friends Jeremy and Camilla Fry. (Yes, the couple in which Armstrong-Jones is depicted as having a threesome with in the series.)

"When they entered each other’s force field of attraction, their mutual gravitational pull was irresistible, and soon they were sexually besotted. That their passionate love affair was completely secret added to its intensity," De Courcey writes of their passionate attraction.

Yet despite their increasing love for each other, Armstrong-Jones continued to conduct affairs, including with actress and dancer Jacqui Chan, his "first real love". He was also involved with actress Gina Ward at the same time he and Princess Margaret was together, right up until their engagement. Chan attended their wedding, in a car sent by 'Tony' and entering through a side door.

Around this time he also fathered an illegitmate child with Camilla Fry, a pregnancy announcement that appears in The Crown. Born just a few weeks after his marriage to Princess Margaret, Polly Fry took a paternity test in 2004 which confirmed the then Lord Snowden as her father.

Jeremy Fry was supposed to be Armstrong-Jones' Best Man at his wedding but was unable to when the press discovered that he had been arrested 1952 for “a minor homosexual offense." The official reason for his withdrawal was "a bout of jaundice".

In October 1959, Princess Margaret received a letter with the news of Captain Townsend's engagement to 19 year-old Marie-Luce Jamagne. De Courcey writes that Princess Margaret begged Armstrong-Jones not to propose so she could assure the public she was over her former lover.

He proposed soon after with a £250 ruby ring, after seeking the Queen's approval over Christmas. She approved - both her and the Queen Mother got on well with him - but asked them to delay the announcement until after the birth of her son Prince Andrew in February 1960. Their engagement was announced six days later.

The public loved the couple together, all eager to see Princess Margaret happily married after the ordeal with Captain Townsend. Many of the public and media were on their side.

The wedding, the first Royal wedding to be televised, was held at Westminister Abbey on May 6. Armstrong-Jones father, his wife and two ex-wives were in attendance, as well as his former lover Chan. Princess Margaret famously did not invite any Clarence House staff who had looked after her for years, many of whom were not sorry to see her leave.

Their union was also groundbreaking with Armstrong-Jones becoming the first commoner to marry into the Royal family in over 400 years, a move that helped make some of the more recent royal marriages including Prince William and Kate Middleton's seem less scandalous.

On paper, it looked like Princess Margaret would finally get her happily ever after. In reality, it wasn't so.

"In the heady excitement of being able to be together openly, Margaret and Tony never stopped to think of what difficulties could lie ahead," writes De Courcey.

The biggest problem?

"As one friend put it sadly, 'They were both center-stage people, and only one person can occupy the center at any given moment'."

After a three week honeymoon on the Royal Yacht Britannia, the couple settled down to their new life in No. 10 Kensington Palace, "a smallish, detached 18th-century house on the north side of the palace" until their actual residence, 1A was properly refurbished.

No longer just a commoner, Armstrong-Jones was forced to swap his fashion photographer uniform of jeans and leather jackets for well-cut suits appropriate for official engagements.

The pair became renowned for their glamorous parties and appearances at others, sharing dinner with the likes of the Rolling Stones, Shirley McClaine and a wealth of other actors, literary and media figures. Armstrong-Jones had to give up much of his work, but still took personal photos of the family as well as some consulting and charity work.

In 1961, Armstrong-Jones became the Earl of Snowdon, largely for the sake of his forthcoming son should he ever become King. The couple welcomed David Albert Charles on November 3 1961.

"Tony was immediately besotted with his son, so much so that two months after David’s birth he did not want to leave him and fly with his wife for their planned three-week winter holiday in Antigua," writes De Courcey.

"But as Margaret, who had been brought up largely by nannies and governesses, pointed out, provided little David got his bottle every four hours, he would not mind whether it was his mother or the new, very experienced nanny, Verona Sumner, who gave it to him."

LISTEN: The Crown season two and everything you need to be watching this week. Post continues after audio...

Still, friends close to the couple soon noticed cracks appear in their marriage in the form of arguments and "jokes" that were actually quite hurtful digs.

"In the late summer of 1963, when they were invited by the rich Greek shipowner Stavros Niarchos to stay on his private island of Spetsopoula, friends on a nearby island held a party to celebrate Margaret’s birthday, August 21. Tony arrived, bringing with him a present for everyone except his wife," De Courcey writes of one such example.

""Later a barbecue was planned, and the Princess shouted from upstairs to Tony, 'Oh, darling, what shall I wear?' He replied, 'Oh, I think that ball gown you wore last week.' Margaret, knowing it was a celebration, aware of the grand Niarchos style, and brought up in ball-gown culture, suspected nothing and arrived downstairs dressed to the hilt to find everyone else in jeans and sandals."

Pregnant with their second child, Princess Margaret became increasingly "possessive" about Tony and his whereabouts. As a result, he would come home later and later and shut himself away in his workroom or office.

"His low boredom threshold, his solipsistic view of the world, his need to be surrounded by the witty and beautiful, his instinct to push away a woman if he felt hemmed in by possessiveness or “clinginess,” and his scarcely conscious determination to do something or meet someone only when he wanted to meant that he would often refuse Princess Margaret’s demands that he 'come and meet X'," writes De Courcey.

"On these occasions, he would shut the door and remain out of sight, leaving the imperious Margaret at a loss."

The birth of their second child, Sarah Frances Elizabeth on May 1 1964 provided a temporary fix, but the marriage remained a turbulent one.

Lord Snowden took to work to escape royal duties, and began photographing for the Sunday Times. It wasn't just celebrity portraits though - he was known for his documentary style photos on various social issues including poverty and disability.

In his obituary in The Guardian, one such instance was recalled.

"That empathy was most vividly revealed in 1966 when he rushed, well in advance of the dictates of royal protocol, to comfort the relatives of victims of the Aberfan disaster, sitting with bereaved parents and making them cups of tea over several days after a slipping coal slurry tip engulfed the South Wales village school."

Work took him away more and more (frequently with female assistants and lady friends) and the period spent apart caused the couple to drift. Princess Margaret also took lovers while he was away, even allegedly propositioning on of Lord Snowden's closest friends. She had an affair with her daughter's godfather Anthony Barton and was rumoured to have been romantically involved with Mick Jagger, actor Peter Sellers and Warren Beatty.

When they were together, the digs continued.

"At parties, he would cut her off in mid-conversation. “Shut up and let someone intelligent talk,” was one such sally. Another note, from husband to wife, apparently read: “You look like a Jewish manicurist and I hate you," Bates wrote in The Guardian.

They separated in the mid 70s before formally announcing their divorce on May 10 1978.

"Her Royal Highness The Princess Margaret, Countess of Snowdon, and the Earl of Snowdon, after two years of separation, have agreed that their marriage should be formally ended. Accordingly, Her Royal Highness will start the necessary legal proceedings," a statement from Kensington Palace read.

The divorce earned Margaret negative publicity although her romantic life continued to dominate the media, including her relationship with playboy Roddy Llewellyn, 14 years her junior. She passed away after a series of strokes in 2002.

Snowdon remarried almost immediately to one of his former assistants, Lucy Lindsay-Hogg. The pair had been having an affair for several years prior to Snowdon's divorce. They separated in 2000 after Lindsay-Hogg had had enough of his adultery, with several affairs. One culminated in another son born in 1998. He died, aged 86, in January 2017.