Opera is a conceit. Its events play out in a rarefied reality where everybody sings, constantly, their outward concerns and inner turmoil translated into melody that, for the most part, only we can hear. It’s a simple, unproblematic conceit, one that makes a solitary kink in reality but leaves it otherwise unaffected. In his new opera Föreställningen (The Performance), the world première of which kicked off this year’s Baltic Sea Festival in Stockholm, Swedish composer Sven-David Sandström adds an extra conceit: that essentially no music has been composed since around the middle of the 19th century. Instrumentally, the line-up is modestly but recognisably of our time, its string quartet, clarinet and piano joined by a sizeable battery of percussion, dominated by vibraphone and gongs. But the musical language is one in which late (and even mid-) Romanticism and the multifaceted machinations of subsequent modernity have simply never happened, suspended in an aural aspic containing morsels of bygone idioms.

If one squints a bit and affords the piece some generosity, there’s a potential benefit to this peculiar approach. Performed in the intimate Rotundan space within Stockholm’s grand Royal Opera House, to a libretto by the celebrated Swedish poet Katarina Frostenson, the work is situated in the famous Pitié-Salpêtrière Hospital in Paris, where neurologist Jean-Martin Charcot worked with female patients suffering from what was then termed ‘hysteria’. Alongside the treatment, Charcot encouraged the patients to express themselves in performances at masquerade balls, and Sandström’s opera focusses on three women, ​Ann, Henrika and Zora, as they gather to discuss and squabble over their respective costumes. Perhaps then, these women, shut off from the outside world, possibly of limited education and to an extent – either prior to their treatment or in part because of it – mentally impaired, might be well suited to a musical grammar boiled down to a smorgasbord of the simplest tropes from the Baroque, Classical and (early) Romantic periods.

However, despite the rigour of the work’s composition (which never quite becomes all-out pastiche) and the, frankly, stunning performance by the trio of sopranos Miriam Treichl, Katija Dragojevic and Jeanette Köhn, this argument becomes implausible for two reasons. First, being set in the late 1880s makes the work’s appropriated harmonic and gestural palette feel somewhat arbitrarily mannered, an affectation that doesn’t ring true. But far more importantly, the narrowness of this palette proves unable to convey convincingly the very real and raw drama playing out on stage. Like a cross between Marele Day’s novel Lambs of God and Ben Wheatley’s film A Field in England, the opera gives the impression that these three women are all alone in a kind of parallel universe, in which the normalities of social discourse and interaction have become broken down and bastardised, where randomly pulling shapes and assuming strange tableaux vivants have become ordinary, everyday modes of expression. Grotesquery and bleak melancholy are everywhere; quite apart from the performance being prepared for, the one we are witnessing is of three women each in their own ways very deeply damaged.

Unfortunately, Sandström’s music simply cannot cope with this level of psychological wounding. The appropriated musical language, rooted in the most plain triadic movement with hardly a chromatic note to be heard throughout, feels entirely a priori, paying the drama lip service rather than serving it at a fundamental level, putting a gloss on its endemic suffering. There are one or two moments (all when the voices fall silent) when Sandström rises above this, the ensemble articulating music altogether more mysterious and austere, briefly tapping into something that, both musically and psychologically, hints at far greater depths. Frostenson’s libretto clearly wants to penetrate these depths and expose the sharpness and complexity of their pain, yet Sandström affords only these most frustratingly ephemeral glimpses of it. Therefore, although Föreställningen certainly gives these poor women a voice, it drastically restricts their capacity to speak, and the authentic nature and extent of their dark torment is thereby fatally undermined.