Kristen, Linda and Mischa turn out for society bash 12 JULY 2006 The beautiful people were out in force for the Serpentine Gallery's annual summer party, traditionally a highlight of the London social calendar. Actress Kristen Scott Thomas, supermodel Linda Evangelista and 'It' girl Camilla Al-Fayed partied alongside young royals including Lady Gabriella Windsor and Marie Chantal of Greece. Tuesday's exclusive bash in London's Hyde Park lived up to the star-studded guest lists of previous years, attracting a mix of film, fashion and arty types. A pink theme gave a romantic glow to the contemporary art gallery's lawns which were bathed in rose-coloured light and adorned with pink flowers, courtesy of sponsor Yves Saint Laurent. The luxury label was worn by several glamorous beauties on the night including The English Patient's Kristen who stepped out in a YSL champagne-hued sheath with black and white bead detailing. Pregnant supermodel Linda also donned the designer's finest, covering her bump with a fabulous Boadicea-style gown. Looking radiant at six-months, she was still keeping mum about the father's identity. Also among the 1,000 guests paying