The tormented king (the frightful Philip II) fears his son Carlo is plotting against him, so he calls up the Grand Inquisitor and asks if he has the right, the justification, to have his son killed. “Why not?” says the priest. God did. Then he and Philip lay on an IS-style mass-execution of heretic Flemings to make a point about peacekeeping.

I am afraid the Church does not come too well out of Giuseppe Verdi’s political drama, based on a typically fiery play by Schiller. Set in Spain against the backdrop of the sixteenth-century Spanish-Catholic genocide in Flanders, the opera adds romantic anguish and a spot of Grand Guignol to the mix.

Carlo has had the briefest glimpse of happiness with the French princess Elisabetta, but a peace treaty means she must marry his father instead. Carlo’s friend, Rodrigo, full of humanitarian fire to save Flanders, tries to recruit the lad away from the court where his misery grows every day. Meanwhile, in the monastery of San Yuste, where the late Emperor Charles V (Philip’s father) retired and died, a mysterious old monk intones fatalistic dirges of failure and futility.

The gloom of this Spanish horror suited Verdi brilliantly. Now in his fifties, he had left behind the crash-bang of his early work, wrote operas only once every five years, but his metaphysical pessimism was deeper than ever. on Carlo – father against son, women against men, Church against State, State against people – provoked a music-drama built of intense encounters and conversations that goes to the heart of the world’s deceptions.