As unions between a multi-married Hollywood star and one of Europe's wealthiest money-makers, philanthropists and social gad-abouts go, the confirmation could not have come in a more po-faced way. "The engagement is announced," read yesterday's personal columns of The Times, "between Arpad, son of Mr Pascal Busson, of Paris, and Mrs Florence Harcourt-Smith, of South of France, and Uma, daughter of Mr and Mrs Robert A F Thurman, of New York."
Put like that, you'd think they were two sweet young things newly embarked on life's rocky road together. But that is not quite the case. She is Uma Thurman, 38, statuesque star of Pulp Fiction and the Kill Bill movies, formerly married to actors Gary Oldman and Ethan Hawke, and ex-companion of New York hotelier André Balazs. He is "Arki" Busson, former consort of supermodel Elle Macpherson (pictured with Busson, below), one-time gentleman caller to Farrah Fawcett, worth £250m through hedge-fund activities, and one of the world's most effective networkers.
So it's not surprising what they see in each other. Nor, given the circles in which they move, how they met: at a dinner party in Milan co-hosted by Gianni Versace and Tony Blair. Since then, as they edged towards "making a spousal commitment", as Hollywood Today archly put it, they have regularly popped up at fancy affairs, managing both Nelson Mandela's and Elton John's parties last week.
These gatherings are as nothing compared to the happy couple's rococo antecedents. Uma's grandfather was a German nobleman, and her mother a model who was briefly married to LSD advocate and Sixties dissident Timothy Leary. They had been introduced by Salvador Dali. She then married Robert Thurman, a New York academic and the first Westerner ordained as a Tibetan Buddhist monk. The Dali Lama was an occasional house guest.
Busson's family is just as remarkable – father was a French army officer and Algeria veteran, mother an English debutante. Arpad was named for Arpad Plesch, his step-grandfather, who, when his first wife died, married her daughter. A rich Hungarian financier, he was, potentially, the black sheep of the family, being "linked", as professional insinuators put it, to the Nazi-era, Zyklon-B producing firm IG Farben.
Young Arpad did his national service as a nurse, and then embarked on a life in society and finance. His firm EIM invests in other hedge funds, and he deploys his skills and contacts to make enormous sums for good causes. His charity Absolute Return for Kids (ARK) has raised nearly £100m, and spent most of it on Aids care in South Africa, orphanages in Romania and Bulgaria, and education in India and the UK.
Both Thurman and Busson have two children from previous relationships. She has a home in New York, and he in Notting Hill and the Bahamas. He has also been known to rent out Yorkshire's 45-room Mulgrave Castle for long periods. Even by the standards of The Times personal column, this is quite a match.