THE PLOT thickens at the Hay Festival, with news that Camilla, Duchess of Cornwall will be making an appearance today at the famous literary event.

But Camilla isn’t the only surprise addition to the programme at the Hay-on-Wye books festival. Next Saturday, Wikileaks founder Julian Assange will make a rare public appearance when he gives a talk called, simply, “Wikileaks”. Back on the official schedule, former M&S executive chairman Sir Stuart Rose is due to appear tomorrow, where he will debate whether big business can be sustainable with the chief executive of Co-op, Peter Marks.

Rose, who launched M&S’s eco-strategy Plan A, will argue his case in the capacious Barclays Wealth Pavilion, as Barclays’ wealth management business marks its fifth year as a “key sponsor” of the artistic gathering. “Supporting the literary world reinforces our commitment to thought leadership,” said a spokesperson for the bank, whose executives seized the chance to “engage with clients in a unique setting”.

The biggest draw of the Bank Holiday weekend was rehabilitated Hollywood star Rob Lowe, who lit up a large cigar on arriving by helicopter before being grilled by Sky presenter Mariella Frostrup about his “Icarus-like” fall from grace, as revealed in his new memoir.

Meanwhile, the president of Engine Group Robin Wight, who stepped down from the board of the advertising business when private equity firm HIG Capital took a 40 per cent stake in the group, was the life and soul of the party at the alternative How The Light Gets In festival at the other end of the village.

Wight was in town to listen to the session by his friend John Hegarty, the advertising guru behind the Levi laundrette ads, and he was still going strong in his turquoise patent shoes at 2am. Not bad going: as Wight cheerfully reminded The Capitalist, he is “pushing 70”.

ALSO adding glamour to the countryside was Liz Hurley, the guest of honour at a Friday night gathering hosted by her old friend William Cash of Spear’s, the wealth management magazine described by GQ as “the bible of the banking fraternity”.

On Sunday, it was GQ editor Dylan Jones’s turn to throw a party – jointly with Nick Jones of Soho House – at a country house wedding-style sit-down dinner for 200 at Cabalva, the Whitney-on-Wye home of the Hay Festival’s chair Revel Guest.

Spotted among the trestle tables were Gail Rebuck, chairman and chief executive of Random House Group (pictured left with literary agent Ed Victor and her author Nigella Lawson), as well as culture minister Ed Vaizey and Sunday Telegraph columnist Matthew d’Ancona, who came straight from interviewing David Miliband on “leadership issues”.

HERE’S an offer you can’t refuse: The Capitalist has 200 free tickets to watch team City A.M. New York compete in the Mint Polo in the Park tournament on Friday at the Hurlingham Club in West London.

Following the Twenty20 format that has been so successful in cricket, World Polo has brought in new rules to make the game faster and more accessible even to newcomers.

To apply for passes, please email with the number of tickets you would like, maximum ten per request, giving your email address and phone number.