"It doesn't matter what you do in this bedroom as long as you don't do it in the street and frighten the horses," actress Mrs Patrick Campbell famously declared at a time when adultery was rife in English high society. Her outlook was apparently shared by Idina Sackville, whose life was so scandalous that for many years it was kept secret from her great-granddaughter, Frances Osborne. The inspiration for Nancy Mitford's character "The Bolter", painted by William Orpen and photographed by Cecil Beaton, Sackville had countless affairs, divorced five times and was branded the "high priestess" of "White Mischief" following the murder of her former husband in Kenya. Osborne's vivid depiction of English upper-class life immediately after the first world war is never judgmental, and she handles Sackville's dubious decision-making with real compassion. But it's hard to sympathise with a woman who abandoned her children for a life of bed-hopping on territory snatched from Kenya's indigenous population via a soldier-settler land raffle.