Never mind the naysayers who will tell you that A Village Romeo and Juliet doesn’t work as an opera, that it is inherently undramatic and that it is destined to remain forever a footnote in the annals of operatic history. True, at first glance a tale about two well-to-do Swiss farmers squabbling over a piece of wasteland and bankrupting each other with their pointless legal wrangles would seem an unlikely dramatic backdrop to a masterpiece.

But in the heads and subconscious of the protagonists it’s a different story. Abandon your preconceptions and you may quickly find yourself immersed in tragically exquisite music: make no mistake, this is a gem, no matter it is much underrated, and the 150th anniversary of Delius’s birth would seem as good a time as any for its worth to be reassessed.

Delians can rejoice, then, that this task has fallen to a small provincial town in southern Ireland. The rare chance to see the work on stage was what prompted me to cross the Irish Sea to pay my first visit to Wexford Festival Opera, whose mission over 61 years has been to discover or rediscover neglected, often almost unknown, works.

By rights, we shouldn’t have been in Wexford at all. Stephen Medcalf’s stunning production is based on the one he mounted in Cagliari, Sardinia, 10 years ago. And it had been going to Covent Garden as the house’s anniversary tribute to an unjustly neglected composer – although we’ve heard more Delius this year, much of his work has fallen under the radar. A Village Romeo and Juliet was to have been Sir Charles Mackerras’s swansong. When, two years ago, Mackerras died, the plans were thrown in the air and then, when the Royal Opera House was called on to make 15 per cent savings, they decided to dump Delius and stage in its place even more performances of its 1994 Traviata (was it more than 30 last year?), about which it’s more challenging to try to think of sopranos who haven’t sung their Violetta than those who have.

It was a crass decision and Covent Garden should hang its head in shame. London’s loss was Wexford’s gain. Medcalf completely rethought his production for the much smaller and differently-proportioned Irish stage and the net result is a thoughtful, provocative and intensely moving realisation.

Improbable as it may seem, Wexford is an elegant purpose-built modern opera house with a splendid acoustic. Medcalf uses a single basic set, imbued with layers of symbolism as it gradually evolves through the piece’s six scenes. The opera charts the hopeless love between Sali, the son of farmer Manzi, and Vreli, daughter of the other, Marti. While their fathers tear the pair apart; their fascination with each other deepens. Yet they are constrained by convention, by the profound quasi-religious conviction of their ‘class’ that sexual happiness is to be found only in marriage.

As ever with Delius, his music seems to betray a plethora of apparent influences. I arrived here straight from four nights of the Ring and at times you almost felt this was the fifth, so imbued with quasi-Wagnerian leitmotifs is it from first chord to last. Or was it Debussy or maybe Richard Strauss? And yet, however derivative Delius may sound, at the end you understand that there is an authentic voice here that is his own – a sound that haunts and returns long after the music is a memory.

The last three scenes are pure magic – almost literally so. After Sali has maimed and all but killed Vreli’s father, the couple fall asleep and have identical dreams. They are celebrating a joyful white wedding and their families are at peace. The staging is a brilliant theatrical trick; then after the interval there is a complete shift of mood, the lovers have arrived at a local fairground, populated by acrobats, dancers and human roundabouts. For a while the clowns take centre stage. It is a spectacular change of pace and atmosphere.

But only on the surface. The darkly enigmatic figure of the illegitimate Dark Fiddler, who had he been born in wedlock would have been the true owner of the barren strip, tempts the would-be lovers to break the chains of their class and upbringing. Is he the Pied Piper, or maybe he is the devil?, urging Sali and Vreli to join the free-loving partner-swapping Vagabonds: ‘Follow me and my friends up to the mountains, up there ’tis fresh and free. Your own will reigns supreme and for your marriage bed there’s soft and purple heather.’ He surely holds sway in the Paradise Garden, the spiritually uplifting walk towards which – the famous orchestral interlude – is the one familiar and popular moment in the opera. We watch the star-crossed lovers walking. But when they arrive at their Paradise it is anything but. The Paradise Garden is an unholy, down-at-heel inn: Eden long after Adam and Eve have been expelled and the serpent has done his business. There’s nothing physical stopping the lovers from becoming gypsies and indeed joining the Vagabonds, but Vreli is much too psychologically conditioned and the heartbreaking apotheosis is their own inevitable ‘Liebestod’.

The psychological drama is realised here by an uncommonly fine orchestra handled with deep sensitivity by Rory Macdonald, who has the benefit of a first-class cast of singers. Wexford’s Dark Fiddler is David Stout, who was to have sung the role at Covent Garden, and his finely judged menace is so understated that there is a disconcertingly sinister feeling as he repeatedly pops up to inflict ‘coitus preventus’ at awful moments. His apparent fiddling is so finely honed that there were plenty in the audience wondering whether it was actually he himself playing so hauntingly on his violin. Not bad for someone who picked up the instrument for the first time only a month ago.

John Bellemer and Jessica Muirhead are ideal as the lovers, well-matched, starkly convincing. Muirhead is a star waiting to happen: she understudied Miah Persson as the Governess at Glyndebourne but her break didn’t come. Here she takes the breath away, hitting her fearsome top notes with a seemingly effortless ease and gorgeous tone, revelling in Delius’s challenging vocal line. But always it is within the context of the emotional turmoil that lies at the heart of the work and of her deeply moving interpretation. Muirhead has penetrated the soul of Vreli and her moving, very special performance, was alone worth the journey.

‘She sings with so much heart,’ Rory Macdonald agrees. ‘Delius’s music is so chromatic that a lot of it is very difficult to sing. And the range of both the main roles is very wide, and a lot of it is very low, so you have to have voices with enough heft to carry over that big orchestra, especially when they are in the lower register. At the same time they have to seem young. And both of them really love the opera, as does David Stout, and it really shows.’

Others may disagree, but for me this was the single most moving performance I’ve seen all year. Overall, a fabulous rendering of an opera which, difficult though it may be to realise, deserves a place at high table. And, in Jessica Muirhead, the discovery of a thrilling soprano talent.

Read more about this year's Wexford Festival Opera in the December issue of Gramophone, published on November 30.