Carmen has always been in my head as a “pretty” opera: lovely tunes, colourful setting, exotically alluring gypsy brushing up against hunky bullfighter and handsome soldier - not exactly French Grand Opera, perhaps, but a far cry from gritty verismo. Calixto Bieito changed all that last night, with a production for ENO that strips the story down to its bare essentials, and left me thrilled beyond measure.

In Bieito’s conceit of the opera, the barracks of Act I is no cosy place: it’s full of rough, sex-starved squaddies, and the air is thick with threat. The characters are different from their usual stereotypes and inifinitely truer to life: Micaëla is no shrinking violet from back home but a confident girl who may ultimately fail to win back Don José but gives it a damn good shot; Carmen is no exotic figure of unnatural sexual power but simply a tart who takes her men where she can; Don José isn’t the weak-willed lad in thrall to Carmen’s powers but a dangerous, violent obsessive.

It all hangs together and gives each act a single focus of raw emotional power: the threatening repressed sexuality of act I, the sleaze of the smugglers’ den in Act II, the passions of broken love in Act III and the mayhem of the crowd in Act IV - followed by a very quiet, very personal killing. Sets are extremely sparse, all over a plain flooring that might be sand or baked mud. In Act I, a flag pole and a phone box are enough to depict the barracks; in Act II, Lillas Pastia’s tavern turns into a single beaten up car parked in a desolate lot somewhere; Act III is dominated by the giant figure of the Osborne Bull; Act IV is a simple circle in the sand, drawn by Lillas Pastia, who forms a sort of eminence grise masterminding proceedings.

If only, if only the musical performance had been up to the standard of the production. Sadly, the ENO’s usually reliable orchestra had a serious off night. There may not have been anything wrong with conductor Ryan Wigglesworth’s tempi or intent, but the playing was anaemic, lacking in accenting and bite. The staging of Carmen may respond well to a sparse, bleak approach, but the music does not: it needs an injection of energy that simply wasn’t there last night - except in the chorus numbers, where the ENO’s chorus gave it their all, resulting in the injection of thrills and excitement that had otherwise been lacking.

Only the least significant of the four main roles impressed: Elizabeth Llewellyn’s Micaëla showed strength of voice and character, with warmth and depth beyond what we’re used to. Ruxandra Donose, I felt, was horribly miscast: she is attractive and has a lovely voice, but the essence of Carmen’s sex appeal is danger and abandon, while Donose sounds far too safe and pretty. Leigh Melrose sang Escamillo’s high notes well enough, but vanished in the lower register and didn’t produce the required swagger while Adam Diegel acted Don José with character but never really hit the heights vocally.

Bieito has been staging Carmen since 1999, but this is the first time that he has done so in London, and plaudits to ENO for bringing him over. He has two big advantages over Bizet: he’s actually Spanish, and he isn’t bound by the conventions of Paris society of the 187os. The critical response to Carmen in 1875 was vitriolic: even given a production that would undoubtedly have been extremely tame by today’s standards, critics were scandalised by the advent of such a low-life scenario on the operatic stage. The public didn’t agree and flocked to the production, but it didn’t prevent Bizet from being an embittered man when he died three months after the opening. This production may be “concept theatre”, but for me, it’s a concept that’s buried inside the original waiting to get out. Bizet pushed the envelope as far as he dared for his own time, and Bieito’s development feels to me like what Bizet might have done given the freedom to be harder hitting. It’s also far closer to the spirit of Merimée’s original novella (which is definitely recommended reading) than anything usually staged.

Five stars for the production, two for the music. Let’s hope the musical performance improves during the run - because if it does, this will make for a sensational night’s opera.