'The Blue Beast'—Edwardian slang for sexual passion—is the true account of the intimate lives of three extraordinary Edwardian women. Drawing on private family archives and highly revealing letters and diaries, the story examines how they became mistresses or confidantes of some of the most powerful men in Britain, men who profoundly affected the Empire's efforts in the First World War. The wealthy and voluptuous American adventuress, Emilie Grigsby, claimed she was the 'mascot of High Command' – and not without good reason. She courted the press baron Lord Northcliffe, the philandering Quartermaster-General, Sir John Cowans and The Times military correspondent, Colonel Charles Repington, all of whom fell under her spell. It was manipulation on an ambitious scale, although eventually her schemes unravelled. Meanwhile, the sensuous and statuesque Winifred 'Wendy' Bennett launched into a passionate affair with the Commander-in-Chief, Field Marshal Sir John French. 'The 'Blue Beast' uncovers how they conducted their relationship, whilst French wrestled with crisis after crisis to keep command of a vast army on the Western Front. Finally, the strong-willed and aristocratic Hon. Sylvia Henley replaced her sister Venetia Stanley as the close confidante of Prime Minister Asquith. It brought her great influence; but it was no compensation for the personal heartache that followed. Taking the reader on a journey into London's High Society during the glittering Edwardian era and the tumult of the Great War, Jonathan Walker uncovers a story of power, passion and betrayal.