Mozart wrote Lucio Silla as a teenager: an extraordinary achievement. Although it can’t lay claim to the emotional dexterity and acute social awareness of his mature works, it’s an ambitious piece which demands a great deal of its primarily soprano cast, taking as its theme the life of the Roman dictator Sulla, here “Silla”, though with only the most nonchalant nod to the facts of history (Cinna, a key character here, had already been murdered well before the putative action of Giovanni de Gamerra’s libretto). Silla is, for de Gamerra’s purposes, a tyrant ready to undergo a proto-Enlightenment personal revolution of his own, changing tactics from murder to universal forgiveness on the basis that there’s no victory like a PR victory. This fits with Plutarch’s assessment of Sulla as a self-serving egomaniac, able to charm at will when he perceived a need, yet entirely callous to the world otherwise; and it’s true that Sulla did technically resign the dictatorship a few years before his death, although sadly we can’t ascribe this (as Mozart’s opera does) to the spontaneous expansion of his soul. However, this work speaks more (to us) about the history of Mozart than the bloodied final throes of the Roman Republic.

Lucio Silla remains fascinating for three reasons. First, as the culmination of Mozart’s extraordinary youthful career as a child prodigy, it is a bewildering demonstration not only of his genius, but of the extent of his exposure, and sheer hard work, as his father dragged him around the courts of Europe. Like other child stars, the actual nature of Mozart’s “childhood” was peculiar: Lucio Silla seems to come from the hand of a musically seasoned artist, not a boy. Its scope is vast (Buxton’s performance significantly reduces the original 4-hour score, which comes with an optional extra hour of ballet music!), and its arias daringly difficult, requiring sopranos to somersault across vocal registers, maintaining exceptional control, with every aria doubly repeated. This vastness, and the endless da capo repetitions, do make it dramatically unwieldy, and emotions are painted rather simply into the score; still, it’s a breathtaking illustration of his gifts at this early stage. Secondly, despite Mozart’s comparative youth, the music is not just recognisably Mozart: it is characteristically Mozart. Much of his operatic vocabulary is already present; later, he will wield it with more subtlety and grace, but you can hear exciting foreshadowings throughout. Thirdly, it is a specific source for Mozart’s humane masterpiece La Clemenza di Tito, which takes a similar conundrum of power and mercy as its motive: as the later plot and characters are inversions of this early work, it’s fun to trace the changes from one to the other.

Buxton International Festival have assembled an exciting young cast, and their singing was the glory of the evening. The drama was necessarily lumpen; director Harry Silverstein did as much as he could, but those huge arias (and their endless repetitions) meant we had a parade of singers almost leaving the stage, then turning back, then almost leaving again, then turning back again, as if trapped for extended periods by an invisible forcefield. Stagecraft consequently feels static and repetitive, while Linda Buchanan’s stark, placeless setting, consisting of scaffolding with a few torn, graffitied tarpaulins (signifying civil war), a marble floor and the odd gilt faux-Versailles upholstered chair doesn’t help. Brutal minimalism works for intense psychodrama; but this floundering plot really needs more narrative clarity on stage. Costumes are similarly confusing, with Silla in frogging, brocade and epaulettes, while everyone else looks like they’re at a 1980s cocktail party; but as it’s hard to see how this drama could ever be compelling, music accordingly becomes our focus. The sumptuous tones of The English Concert, conducted by Laurence Cummings, injected as much energy and verve into proceedings as they possibly could.

The four leading sopranos had the best of the evening, with fabulous projection and tone across the board. The two trouser roles (Madeleine Pierard as Cecilio and Karolina Plicková as Cinna) were exceptionally well portrayed, with brilliantly observed male body language. Pierard’s lyrical soprano was beautifully expressive as exiled husband Cecilio, while Plicková’s impressive Cinna constantly grew in assurance and depth as he searched in vain for someone else to kill the tyrant before failing in his own attempt. Rebecca Bottone was well up to the vocally dazzling task of Giunia, Cecilio’s wife and the proud rejector of Silla’s unwelcome love. Fflur Wyn’s warm, expressive and tender soprano was exceptionally appealing as Celia, Silla’s surprisingly lovable sister. Joshua Ellicott, in the title role, exuded more petulance than dictatorial menace, and seemed genuinely relieved to hand his power back to the people; burnished colours from the Buxton Festival Chorus glowed in their triumphal final hymn to liberty. Astonishing music-making, at such luxurious length, is not an ideal first opera experience, but for seasoned Mozart listeners, it was certainly an intriguing evening.