First published in the Guardian on 15 August, 2018

Lads in tracksuits hurl themselves across the stage, all hoods and fists and aggro. There’s no music but screeching sirens and the dense thuds of bodies hitting floor and each other. Then the overture kicks in with a brute shock of sweet-voiced lutes and harpsichords. The contrast works like a punch in the gut, and the audience lets out a collective gasp.

Musical and moral collisions abound in any production of The Beggar’s Opera. John Gay’s 18th century satire is a gleeful period piece of irredeemably patchy values: heartthrob villain who makes gang crime look sexy and misogyny look cute; clingy damsels who paint a flagrantly unreconstructed portrait of the female psyche – meek or manipulative, or both. But The Beggar’s Opera is also a riot and a farce, wickedly funny when done right. It’s the original musical packed with tender airs and lusty sing-alongs. What’s a director to do? Ditch it? Dodge it? Rewrite it?

A new account directed by Robert Carsen with stunning period-instrument accompaniment from Les Arts Florissants opts for the rewrite tactic without losing sight of the original. The text is updated (sharp new words by Ian Burton) as a 21st century East End crime comedy. The cast, all of them singer-actors from the musical theatre world, can deliver proper bawdy when required. Dirty language and Brexit satire set to elegant baroque tunes – the production, which comes to the Edinburgh International Festival this week, has been billed by EIF a Beggar’s Opera “for our own turbulent times”.

That billing turned out to be more accurate than the EIF marketing department could have imagined. The production was created for the Théâtre des Bouffes du Nord in Paris, a house made famous in the 1980s when director Peter Brook turned it into a hotbed of pared-back, provocative theatre. The building is a fading beauty on the tracks of the Gare du Nord, not far from the Canal Saint-Denis in the north-east of the city. These days the waterway is crammed with hipster brasseries and boules courts; it’s also the site of some of the starkest human rights failures in modern Europe.

In the past year, thousands of migrants and refugees have been living in makeshift tent villages under bridges along the canal. Aid workers have described “catastrophic sanitary conditions” and reported thieves, abusers and people traffickers targeting the camps. Bouffes du Nord is a stone’s throw away — walking to the theatre along the canal, it was impossible to avoid the appalling deprivation of the camps. So when the first image in Carsen’s production is a homeless man huddled in a sleeping bag against a cardboard box, the appropriation of poverty as theatrical gesture was glaring.

“It is a problem,” Carsen acknowledged, speaking a couple of weeks later. “But problems are not to be ignored. The Beggar’s Opera was written as a rebellion against grandiosity. Everything about it questioned perceived morals of the time. Gay wanted to expose the hypocrisy of the elite and of politicians, to provoke debate by romanticising the shifting morality of criminals. This piece reflects all levels of society. Yes, I was aware that constructing the image of a homeless person on stage would have added resonance given the situation in Paris right now, but it’s an opera about the real world. I think it’s right that we don’t flinch away from what we see on the streets.”

And indeed, The Beggar’s Opera stirred things up from the start. It opened on Drury Lane in 1728 and was an instant hit, performed in Dublin, Glasgow, New York and Jamaica – and every year in London for the remainder of the 18th century. Audiences loved the tunes. They left the theatre humming the medley of pop songs that had been loosely arranged for the opera by Johann Pepusch. But that wasn’t all. There is no other opera remembered by the name of its librettist rather than its composer. The great appeal of The Beggar’s Opera was that its commentary felt real, that Gay had dared to tell the jokes that others didn’t, that nobody was spared. If opera was supposed to be about gods and noblemen, Gay made thieves and prostitutes his leading lords and ladies. His libretto held a mirror to high society by turning class values topsy-turvy and spelling out real-life corruption cases that implicated everyone up to the Prime Minister Robert Walpole himself — who went to see the opera, hated it and banned its sequel.

Thus launched 300 years of an opera whose essential remit is to confront the uncomfortable. And for all its clever updating, Carsen’s production remains fairly faithful to the original concept: contemporary vernacular, contemporary satire. The action is transplanted to London’s 21st century underbelly, where the chief of police snorts cocaine off a baby carriage and Jenny Diver plays icy dominatrix in a latex cat suit. The libretto gets a neat overhaul — “let the council work their butts off / we only want to get our nuts off” — and the Brexit jokes come thick and fast. Digs at the phrase “strong and stable” got a wry laugh from the Paris audience.

What doesn’t update quite so neatly is the gender politics. Women in The Beggar’s Opera are brassy matriarchs (Mrs Peachum), devious vixens (Jenny Diver) or pretty fools (Lucy Lockit and Polly Peachum). Carsen admitted to heated debate in the rehearsal room over what to do with these caricatures, and revealed that since since the Paris run he has “toned down the girls’ obsessive qualities”. But ultimately, the values of the piece are ingrained. ”In the age of #MeToo,” Carsen concluded, “not everything has to be bent to fit.”

Beverley Klein, who plays Mrs Peachum, told me she found the dynamics problematic. “We noticed ourselves trying to contrive ways of changing it,” she said, “but in the end these are the characters and this is the story. No matter how far you meddle with the text and try to inject the women with agency, you just have to accept their fates if you’re going to do this opera. I mean, I’m playing a traitorous elderly prostitute. I never thought I’d be hauling myself around in a plastic miniskirt at my age.”

Matters of period authenticity are more malleable when it comes to the music of The Beggar’s Opera — not least because there are no original orchestral parts, only indications of where the big tunes should go. Any new production needs to make a call on how to reconstruct the thing. Brecht and Weill rewrote the music in the 1920s and rebranded it the Threepenny Opera. Benjamin Britten made a neat performing version in the 1940s. There have been settings in Rio slums and all female Japanese troupes.

The music for Carsen’s production was prepared by William Christie, pioneer of historically-informed performance practice, who enthused avidly about his decision to work with musical theatre voices rather than baroque specialists. “Nobody knows what the sound was like for the original productions,” he told me, “so authenticity becomes a grey area. We’re certainly talking about singers who could act. Back then there was no distinction. We’re talking about simple song – call it folk song, or pop music of the period. It was a kind of music that didn’t require trained voices. It was opera for the public, opera to debunk operatic style. So why would we use operatic voices to sing it now? We’re on the right side of authenticity, certainly compared to singers who sing the hell out of it as though it were Mozart.”

And the band? Christie describes a “1930s Duke Ellington setup. We’ve fashioned an improvising orchestra of individuals who can riff and swing. Only the odd solo is written out. It’s the first time it’s ever been done like this and it required the absolute best players who can take on that kind of agency.” For all the scabrous Brexit jabs and plastic miniskirts, it’s this musical collision – live-wire baroque improv meets musical theatre – that might just prove the most daring aspect of the production.

The Beggars’ Opera is at the King’s Theatre, Edinburgh, 16-19 August