SHE was an 'It' girl of 1960s London. He was a gay painter who would become one of the giants of world art.
The unlikely bond between femme fatale Henrietta Moraes and Dublin-born Francis Bacon produced over a dozen paintings, one of which is expected to fetch more than €20m when it is brought to auction next month.
Having spent the past 30 years in a New York private collection, the 'Portrait of Henrietta Moraes' will go under the hammer on Valentine's Day, February 14, as the highlight of Christie's auction of post-war and contemporary art in London.
While the anticipated price tag is enough to draw attention to the sale, the story of the lives behind the painter and his muse is even more intriguing.
Henrietta was the undisputed queen of bohemia in Soho in the late 1950s and 1960s, living a hedonistic lifestyle of nude modelling, drinking, drug-taking and many dalliances.
Born Audrey Wendy Abbott to an officer of the Indian Air Force in 1931, Henrietta had an unhappy childhood, raised by a disciplinarian grandmother in England, before attending secretarial school.
She was just 18 when she married an older man, the filmmaker Michael Law, then she wed the actor Norman Bowler before turning to a younger husband, the 18-year-old poet Dom Moraes (she was 25).
In her autobiography, she claims Mr Moraes went out for cigarettes one day and never came back.
She was a flatmate of singer Marianne Faithfull for years and had a brief career as a cat burglar for which she served time in Holloway Prison.
But her career as an artists' model will ensure she is never forgotten.
She was briefly a lover of Lucian Freud who painted her on three occasions.
But Bacon is believed to have painted her at least a dozen times and possibly more. The actual number is unverified as Bacon liked to paint from photographs and asked his friend John Deakin to take a number of images of Henrietta.
The large, vibrant nude painting up for sale has been described by Francis Outred, Christie's head of post-war and contemporary art in Europe, as "one of the most seductive and sexually charged paintings I have ever encountered by Bacon".
The image was painted in 1968 when Bacon was embarking on a stormy love affair with George Dyer, who became an important subject of his works both during his lifetime and after his death from an overdose in 1971.
The portrait, which measures over 1.5 metres, has only ever had two owners -- post-war industrialist Willy Schniewind and the present owner who acquired it in 1983, identified as a "distinguished New Yorker".
The auction record for a Bacon was set at Sotheby's in New York in May 2008 when his 1976 painting 'Triptych' sold for $86.3m (€67m).