Imagine that it is the summer of 1936 and you are on honeymoon in Germany. The sun is shining, the people are friendly – life is good. You have driven south through the Rhineland, admiring its castles and vineyards, and have watched fascinated as the huge, heavily laden barges ply their way slowly up the Rhine. Now you are in Frankfurt. You have just parked your car, its GB sticker prominently displayed, and are about to explore the city, one of the medieval architectural gems of Europe. Then, out of nowhere, a Jewish-looking woman appears and approaches you. Radiating anxiety she clutches the hand of a limping teenage girl wearing a thick built-up shoe. All the disturbing rumours you have heard about the Nazis – the persecution of Jews, euthanasia, torture and imprisonment without trial – are at that moment focused on the face of this desperate mother. She has seen your GB sticker and begs you to take her daughter to England.