JK Rowling and Sarah Brown turned on the glamour last night at the annual Raisa Gorbachev Foundation charity gala.
The Harry Potter author wore a stunning sky blue gown while the Prime Minister's wife looked resplendent in a regal purple dress.
It was the second function of the day for Mrs Brown, who arrived to the event at Hampton Court Palace in Surrey fresh from her trip to France for the D-Day commemorations.
The lavish £15,000-a-table do was organised by a committee that includes Madonna, London Evening Standard proprietor Alexander Lebedev and his son Evgeny - who is chairman of the foundation.
Others on the committe include artist David Hockney and Lady Rothermere, wife of Viscount Rothermere, chairman of The Daily Mail and General Trust, which publishes The Mail on Sunday.
The guests - who also included pop star Nick Rhodes of Duran Duran, Blur bassist Alex James, singer Rachel Stevens, London Mayor Boris Johnson and comedian Peter Kay - were promised the chance to bid for auction prizes.
These included dinner with Mr Gorbachev in Moscow, a Damien Hirst artwork, a Fiat car designed by pop artist Sir Peter Blake and a cheeky lap dance by comedian David Walliams.
Sir Elton John and U2's frontman Bono have supported the foundation by providing the entertainment in previous years.
Eleven synchronised swimmers in pillar-box red swimsuits and hats braved the chilly weather yesterday afternoon, entertaining guests with a routine in a large natural pool in the grounds.
Also among the guests was Vanessa Redgrave, who has rarely been seen in public since the tragic death of her daughter Natasha Richardson in a skiing accident in March.
JKR and PETER KAY <333
~S Club 7's~ Rachel Stevens and fiance Alex Bourne
Vanessa Redgrave and Sharleen Spiteri
JONATHAN RHYS MEYERS <33 and girlfriend Reena Hammer
Sophie Dahl and Kimberly Stewart
Jamie Cullum and gf Sophie Dahl (omg rofl)
Blur guitarist Alex James and his wife Claire
Host Mikhhail Gorbachev and JKR
Lots more pics are here
JKR and husband Neil