Daniel Hannan is an MEP for South-East England, and a journalist, author and broadcaster. His most recent book is How we invented Freedom and why it matters.

For 15 years, I wasn’t able to watch Othello on stage. All because of a joke. When Tom Utley, the brilliant Daily Mail columnist, was at school, his English master had a theory (mistaken, if you ask me) that there was a mistranscription in Act V, Scene 2. As Othello prepares to murder his sleeping wife, Shakespeare has him say, “Put out the light, and then put out the light”.

Now I reckon that the repetition is deliberate, and means “blow out the candle, and then strangle Desdemona”; but Tom’s teacher was convinced that it was a corruption, and asked his class what the original might have been. Tom, with the air of a man who had given the matter great thought, raised his hand. “Could Shakespeare have meant Othello to say, ‘Put out the cat, and then put out the light?’”

Watching the play at the Whitehall Theatre a few weeks after hearing that story, I saw the line coming, and started to shake with laughter. My neighbours, not unreasonably, began shooting me that dirty look which is as close as British people get to uncontrollable rage, but this only set me off more. The actor playing Othello – a South African, if I remember – carried on with great dignity, while I snorted and whimpered a few feet away.

What made the whole thing especially painful is that the line comes at the dramatic climax of the play. One Victorian theatre-goer was so caught up in the action at that point that he leapt from his seat crying “Stop, ye great black fool, can’t ye see she’s innocent?” The last thing an audience needs is someone pant-hooting like a chimpanzee in the stalls. And so, for years, I stayed away, contenting myself with screen versions – including the unintentionally hilarious 1965 film in which a blacked-up Laurence Olivier, who hasn’t properly grasped what a close-up is, projects to the back of an imagined theatre his peculiar idea of how an African man might walk and talk.

Last week, after 15 years of trying to get that bloody joke out of my system, I decided to have another go, watching Iqbal Khan’s new production at the RSC in Stratford. I needn’t have worried. When the line came, Othello illustrated it by taking two goes to stamp out a candle, causing several people in the audience to giggle. The giggles suggested, to put this as gently as I can, that not everyone had properly suspended disbelief. And the reason they hadn’t is a depressingly common one: the production was far too fussy. There had been rap music and water-boarding; amazing feats of set design, with scenes taking place on water in the middle of the stage; whizz-bangs of every kind – and, as a result, the performance itself failed.

Not that I want to pick on this director; over-produced Shakespeare is the curse of our age. When dealing with the finest lines in this or any other language, you should let Shakespeare do the talking. If you insist on interposing your ego, you ensure that all in the audience, wherever they sit, get an obstructed view.

For example, this was the first time – or the first time I can think of, at any rate – that a black Iago was cast next to a black Othello. The villain was played by the hugely talented Lucian Msamati (Salladhor Saan in Game of Thrones). Now there are plenty of things that a director can do to elaborate the themes of race and alienation inherent in the text. Some years ago in Washington, for example, Patrick Stewart played Othello as the only white actor in an otherwise black cast, an inversion that neatly highlighted the Moor’s perspective for white theatregoers. But if you’re going to do something as bold as switching Iago’s colour, you’d better be going somewhere with it. If all you’re doing is saying, “Look! Race!” then, really, you’re not adding anything.

I’m not saying that we want togas and doublets, far from it. When you stage Shakespeare, you are fashioning a setting for the most precious of jewels. The work demands all your artifice. The goldsmith’s craft may be creative, original, dazzling – but it must be deployed in the service of enhancing the gem, not smothering it.

To give an example, of how to get it right, the Globe has just staged The Merchant of Venice with Jonathan Pryce as Shylock and his daughter, Phoebe, as Shylock’s daughter Jessica. Now MoV has always struck me as among the most problematic of all Shakespeare’s plays, both in its themes and in its structure. But the director, Jonathan Munby, found a way to deal brilliantly with both problems.

First, the thematic problem. If MoV were by any other author, it would no longer be staged. Shylock isn’t just a nasty piece of work who happens to be Jewish. He incarnates – indeed, he may be said to perpetuate and propagate – the nastiest anti-Semitic stereotypes: he is ruthless, clever, greedy, legalistic and anti-Christian. Yet Shakespeare, being Shakespeare, makes Shylock plausible. Contrast the part with, say, Barabas in Marlowe’s Jew of Malta. Where Barabas is a pantomime villain (“I walk abroad a-nights and kill sick people groaning under wells”), Shylock is humanised by his ill-treatment. His “Hath not a Jew eyes” speech is terrifying precisely because it contains enough pathos to make his malevolence understandable.

Every Shylock I have watched on stage or screen, from Dustin Hoffman to F Murray Abraham, had softened the role, giving it more warmth than a bare reading of the text might suggest. Modern sensibilities demand such a gloss.

This is especially true of the trial scene, when it is not one old moneylender who faces judgment, but an entire religion. Repeatedly offered the chance to move from justice to mercy – from the Old Testament to the New – Shylock stands by the literal letter of the law and so condemns himself. So, mediaeval theologians held, did Jews condemn themselves by rejecting Christ’s truth.

Remarkably, this production did not downplay the religious theme. On the contrary, as Shylock sharpened his knife, Antonio was spread out in a grisly echo of the Crucifixion, muttering a paternoster. A moment which most Christian theatregoers find uncomfortable, and most Jews excruciating, was emphasised and elongated. Where, I wondered, could the play go from there?

For, as well as the thematic difficulty, MoV contains a structural challenge. The nastiness in Venice is interleaved with relatively frivolous scenes in Belmont involving suitors trying to pick the right casket. The play ought, in many ways, to finish at the end of Act IV, when spurned, ruined, apostatising Shylock is bundled out. But we are instead treated to some lovers’ games involving rings. How does a director avoid the anti-climax? How, in particular, would this director, who had played the Belmont scenes as camp comedy, escape crashing bathos?

Here is where the originality of a good production can be used to complement rather than detract. Munby had noticed that Jessica is still on stage in Belmont, having not said much for a while, when the play ends. She is presumed, I suppose, to be happy enough with her Christian husband and her new religion, though no one says so.

But this time, instead of the curtain falling, Jessica came to the front of the stage, collapsed in grief, and started chanting the Jewish prayer for the dead. As her lamentation echoed around the courtyard, her father was led in to be baptised, Jessica’s keening forming the descant to the plainsong of the monks around the old man. In that mingled melody were centuries of sorrow. It was hard not to weep.

What’s that? You expected some political message? Some comment on the coming referendum? Well, we shouldn’t always let the immediate crowd out the important, so I’m instead going to leave you with Jessica’s haunting final words: “I am never merry when I hear sweet music”.