At first sight, martyrdom feels an unlikely subject for opera; it is far too profane and fleshly a medium for that. But it is also the most fatal of art forms, full of people dying for their beliefs, willing to suffer every last torment rather than compromise their integrity. Think of Carmen, who willingly embraces her crazed ex’s dagger rather than sacrifice the freedom which is her lodestone. Or Don Giovanni – the anti-Christian martyr, who celebrates a blasphemous Eucharist (“Long live women! Long live wine! Succour and glory of humanity!”) at his own last supper before being dragged, defiantly unrepenting, to Hell by the affronted deity.Once you start this kind of list it becomes endless. Operatic heroines, when not actually ill, nearly always die for love, oft