You don’t need much imagination to list the upsides of an opera house burning down on the first night of a Wagner show. Somehow, Westminster council failed to see that, and stamped out the attractive fire effect English National Opera had planned for the last scene of The Valkyrie. Brünnhilde, the Valk in question, gets put into a magic sleep (familiar to audiences) on a mountain-top surrounded by raging flames. ENO disdained to replace the cancelled fire with anything else, which was weedy, but arguably Wagner hardly needs childish scenic effects since everything you want is right there in the orchestra. Sure, the man himself was all for the tragic scenery and stagecraft of the late 19th century (the only area where he wasn’t miles ahead of the curve, interestingly), and some believe opera houses really ought to give you a bit of visual flimflam for your moolah, but London’s Robespierrean opera bosses like to scour our souls with resolutely dowdy stagings lest we forget for an instant how grim the human condition.

Wotan is a tragic Bill Byron lookalike in a lumberjack shirt and anorak

No fire, then. And it seems the first night was all a bit like that: tough for ENO, for whom nothing ever seems to go right. Different story on the second, however, when everything (except the fire) that didn’t work on opening night clicked, and it became clear that this was a bit of a scorcher, in its gloomy way.

Director Richard Jones is still a kind of talisman in the opera world, though his stuff is generally pretty humdrum these days. A pleasantly offbeat imagination was always his USP, though it can tip into the naff, a genre he fell in love with working backstage on Max Bygraves variety shows. His ’90s Ring cycle at Covent Garden was derided, and apparently he hasn’t developed a higher opinion of Wotan in the meantime. He presents him here as a tragic Bill Bryson lookalike in lumberjack shirt and anorak. But now Jones is a grown-up 68, and I’m glad he’s got another shot at it.

Wagner’s Dark Ages are (as usual these days) sited in the near future: the tiresome touchstone of all opera for the last 15 years being the likes of Cormac McCarthy’s post-nuclear Kerouac retread The Road, and here we are again. On the plus side, I guess these gimcrack references save scene-setting time. In Stuart Laing’s designs, black ash (recyclable, thank the lord) drops from the sky on the crappy cabin where horrid Hunding (Brindley Sherratt) in council-worker hi-vis donkey-jacket roughs up his wife Sieglinde, played by Emma Bell togged out as ’70s Brummie metalhead. (Yes, all this glamour will go down a bomb at the New York Met when it transfers there.) For reasons that seem unlikely to matter, her long-lost brother Siegmund (Nicky Spence), pops up out of the fireplace.

The practical result of this kind of barebones staging is that, deprived of nice horned hats and elemental forests, the singers have nowhere to hide. All the focus is on the musical and dramatic angles – which is good. Whatever went tits-up on first night had been fixed, and conductor Martyn Brabbins got the orchestra to deliver the hour-long first act in one breath, from the first frazzled buzzing tremolo and hammering basses of pursuing fate to the massively untrammelled passion where our reunited twins discover incestual bliss. Spence in particular is a beautifully lyrical singer: most of the Ring is not bellowing but good German song accompanied by modest little groups of strings or winds, the rest of the vast orchestra sitting around waiting, and this Siegmund sings like a poet.

You can get caught up in the huge sweep of The Valkyrie (and the whole Ring) and miss what it’s actually for and about – the dawn of human love as our only weapon against the arbitrary tyrannies of power and violence. In these big conversations everyone gets their say: only the cleverer ones actually listen and learn. Understanding dawns through human contact: Siegmund, Sieglinde, Wotan, Brünnhilde – their perception transformed by what they see and hear. Of course nothing actually gets fixed, but there are glimmerings of the right road.

The Coliseum is half-empty: fill your boots with cheap tickets, this is the stuff

Jones stages these conversations brilliantly. Wotan browbeaten by his wife Fricka (still smartly turned out at least in this wasteland) and her proprieties, understanding too that the petty-bourgeois shtick she belabours him with was basically his own invention; he ranting at Brünnhilde; her eye-opening chat with Siegmund where she learns what love means and returns to Wotan to teach and gently allow him to discover a way out of the enormous mess. Now Jones’s attention to detail pays off: the terrifically freighted relationship between the overbearing father and teen-semi-rebel daughter in her Bayeux tapestry sk8terboy suit, the layers of anxiety, love and sadness in every bar of the music. Rachel Nicholls, small, boyish, vulnerable, is miles away from the Brünnhilde of popular myth, but sings with all the strength and focus of one, can see into Wotan’s heart and motivation far better than he can: completely convincing as the woman who, at the end of Götterdämmerung, finally and appallingly “knows everything”.

And so to the bit you probably came for, that Ride: rather marvellously introduced by a crazed dancer in a field of bloody corpses, frivolous Valkyries harvesting the dead for the mad plan of defending Valhalla in some projected Armageddon, their frisky nags showing the distinct want of a decent remount officer. It’s jolly, of course, and a good payoff for those tracts of chat, but only an idiot would sit through four hours of music in order to get to these five minutes. Thereafter it’s lucky that Brünnhilde and Wotan have grabbed our interest, because the staging effectively falls to bits, what with that fire, plus Brünnhilde being laboriously clipped into a flying harness. But over a fraught half hour the pair allusively work out how to manage the future, and say their laceratingly sad goodbyes.

Wagner’s Valkyrie, of course, is a shattering piece, its fathomless music and imagination carrying you to wild and undreamt-of places – when done right. This great effort won’t do it for everyone, but it’s way better than the old designer nonsense at Covent Garden, and it is actually important in a wholly non-political way that it is entirely home-grown, not an imported singer in sight. Brabbins has regrouped from a first-night shambles to produce something organic and massively convincing. And the Coliseum is half-empty: fill your boots with cheap tickets, this is the stuff.