Conservationist, scholar, soldier, white hunter and fabled lover - Denys Finch Hatton was an aristocrat of leonine nonchalance. After a dazzling career at Eton and Oxford, he sailed in 1910 for British East Africa - still then the land of the pioneer. Sara Wheeler reveals the truth behind his love affairs with the glamorous aviatrix Beryl Markham, and - famously - with Karen Blixen, a romance immortalised in her memoir Out of Africa. ''No one who ever met him'', his Times obituary concluded, ''whether man or woman, old or young, white or black, failed to come under his spell''.