In 1936, Marlene Dietrich, the most highly paid actor in the world, came to London to appear in a movie entitled Knight Without Armour. When she arrived, the story of King Edward VIII's abdication was just breaking in the news.
Edward, who was single and had not long ascended to the throne, had fallen in love with an American woman, Wallis Simpson, who, in addition to the sin of Americanness, was a commoner, a divorcée and, at the time they started seeing one another, still married. A scandal on every count.
This being the case, the only way he could in fact marry her - once she was divorced from her husband at the time - was to abdicate the throne.
Marlene, who loathed Nazism, was deeply concerned that the abdication would weaken Britain's position in relation to Germany should a conflict arise.
And so, being Marlene, she decided to have her driver take her to Fort Belvedere, the King's 'country' home, where, on the very eve of the planned abdication, she would seduce the King - thereby convincing him that it wasn't worth sacrificing the British Crown for another woman.
Her powers of seduction being legendary, it was no idle threat!
I first happened upon this episode on the podcast You Must Remember This, where it was buried in the foothills of her life story.
To me as a playwright - and one who revels in speculative history - the prospect of placing these two iconic characters of the 20th century in the one room, alone, at such a pivotal time for the British Empire, was utterly irresistible.
The more I then read about Marlene, the more extraordinary she seemed - a true force of nature. And the more I read about the abdication, the more complex and confounding its details appeared from the perspective of the 21st century, particularly given what has happened in relation to the royals since, what with Charles's marriage to Di and Harry's to Meghan - an American, a commoner, a woman of colour, a divorcée and a movie star.
Edward had been brought up as the heir apparent from an early age, but within him was something restless and mercurial that resisted the suffocating straitjacket of the kingly role.
Added to this, his handsome appearance - he was widely regarded as the world's most eligible bachelor - meant that he had ample opportunity to play the field. But he just happened to find himself in the vice of history - a vice so tight that there was no wriggle room.
Marlene was one of a kind - talented, beautiful, intelligent, independent, ambitious, utterly driven and possessed of an enormous capacity for sheer hard work. Thumbing her nose at the Nazi regime, at no small risk to herself, she then went on, at the outbreak of war, to perform tirelessly for the troops at the front line.
She was always there for friends in need - cooking, cleaning, giving money and providing all manner of material and emotional support. Her generosity was boundless, as she gave away enormous amounts of money to those in need and made remarkable efforts to liberate Jews from Nazi Germany.
To watch as the paths of these two great icons cross onstage is a rare pleasure - one that I hope audiences will find a charming, diverting, funny and, ultimately, moving evening in the theatre.
To take them on this journey, we have a stellar team: Ramona von Pusch (German-Australian) and Ashton Spear (Canadian-British) under the acclaimed direction of Tama Matheson (British-German-Australian).
'Falling in Love Again' by Ron Elisha is at the King's Head Theatre, 14 January-8 February
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