Isabel Vincent on the two sisters who rescued opera's Jewish stars from the Third Reich in 'Overture of Hope'

London 1937. Two sisters, Ida Cook, a budding romance novelist and Louise, an ordinary typist for the civil service  share a passion for opera. They use their meagre savings to travel to Germany and Austria to hear their favourite opera stars, many of them Jewish. On the eve of World War II these middle-aged spinsters became part of a network that outwitted the unsuspecting Nazis and helped twenty-nine Jewish families escape persecution. Overture of Hope is the story of the Cook sisters' humble beginnings to the great opera houses of Europe and the unlikely rescue missions they undertook. In this episode Gregory Dobbs chats to Isabel Vincent about how the Cook sisters became part of the inner circle of the German opera world, the moral dilemma faced by Clemens Krauss one of Hitler's favourite conductors, and the ingenious methods Ida and Louise used to smuggle Jewish refugees and their belongings out of Nazi Germany.