There is so much second world war on television – history programmes, prestige dramas, celebrity genealogy shows – that you might assume all the most compelling tales have been told already, three or four times over. But not this one. And, oh, what a story it is. If the gay painter Willem Arondeus and the lesbian cellist Frieda Belinfante seem unlikely heroes of the Dutch resistance, that is only because official histories have taught us so little about the true nature of courage. Their incredible wartime adventures, which saved thousands of Jewish lives, are related here by the famously knowledgable...