He is a megalomaniac brute who thinks he can control everything in his domain from the fruit on his trees to his wife's "obedient body". The Boy dutifully creates exotic images of "azurite and gold" on precious parchment, meticulously executed in fine detail.

Medieval art wasn't representational. Stylized depictions were meant to suggest concepts, not literality. Medieval art and modern art have more in common than we realize! Uneducated as she is, The Woman intuits that art can take on meaning of its own. Images can lie, yet also reveal eternal truths.

This, no less, may be what Written on Skin is about, despite the sensational narrative. It operates on several levels at the same time. Ostensibly the action takes place in a medieval manor house. The Protector thinks wealth will buy him eternity. A thousand years later, the lands he knew have been obliterated by "Saturday car parks" and multi lane highways. Even the Occitan has been absorbed into France. In this exquisitely poetic libretto, by Martin Crimp, past and future are superimposed on each other, reinforcing the idea that worldly certainities are impermanent. Things change, but artistic vision is timeless.

This sense of duality operates throughout the opera. The Protector thinks he controls everything around him. The Boy thinks that being an aritst (and presumably a monk) protects him from earthly engagement. Both are trumped by The Woman who wants the Boy to paint a a ""real woman" with passions and eyes that "grow black with love". The boy can see the flecks of gold in her grey eyes, but his eyes, too, turn black. The Protector sees the painting and suspects. The Boy lies to protect the Woman, but she's having no more subterfuge. "I am Agnès" she cries, "I am not a child!"

Benjamin's Written on Skin is a departure from the 19th century idea of what opera should be. Despite the vaguely modern set, and very modern music, Written on Skin is much closer to the medieval approach to art. The narrative is oblique, despite the barbarism in the plot. We cannot, and should not, impose our own ideas on what the Middle Ages "should" be. "Wild primroses and the slow torture of prisoners" as the Boy sings in Act One. Crimp's text is exquisite allegory. Poetry doesn't operate like prose : overstated literalism would kill the gossamer magic.

Thus Benjamin's music operates as poetry, elusively, obliquely, but with enough passion to make the drama progress even when the words seem static. Illustrations in medieval manuscripts depict cataclysmic scenes as if they're suspended in time. Perhaps in a past incarnation Benjamin painted illuminations, where detail is captured with surreal intensity. Although Benjamin's writing makes a virtue of ambiguity, his orchestration is stunningly pure and clear textured. Low timbred strings like double basses, and a viola de gamba, high pitched keening woodwinds, a glass harmonica and an unusual percussion section which includes bongoes, a whip and Indian tablas. This replicates the clean outlines of medieval illumination : no muddy shadows, but intense, unnatural colour. The percussion also suggests the vigour and simplicity of early music. We can "hear" the musicians of the Occitan in the sophisticated Royal Opera House orchestra. It's curiously unsettling, but perfectly in keeping with the opera. Benjamin himself conducted.

As in their previous opera, Into the Little Hill, Benjamin and Crimp use indirect speech. Phrases like "Said the Boy", or "Said the Woman", are embedded to the text, intensitfying the unsettling sense of allegory. Yet character is very well defined. The Boy and the Woman are playing the roles the Protector wants them to enact. Their long, wailing lines with strange distorted syntax suggest the stylization of mystery plays, or even Greek chorus. Individual words are gloriously embroidered and illuminated, so they shine out from the background of undulating rhythms.

Bejun Mehta sings the Boy, his countertenor at once disturbing and beautiful. Barbara Hannigan sings the Woman, her part even more demanding because the personality develops so dramatically. It is she who is the catalyst for action. As the Woman sits bowed but uncowed, Hannigan's voice expresses the frustration the Woman cannot articulate. When she suddenly pounces on the Boy, Hannigan's voice explodes with sexual tension : animal-like but desperate. She throws herself at her husband who, despite his macho image, can't cope with her being anything other than "pure and clean". At this point, Benjamin's music for the singers changes. The Protector (Christopher Purves) now gets the long, wailing legato, where previously his music erupted in short, brutal staccato. Now Agnès has the short, punchy lines and spits them out with new-found assertiveness.

When the Protector kills the Boy, we can hear his compromised feelings in the music. Is the Protector himself secretly attracted to the Boy? Purves sings with a strange tenderness suggesting that the Protector might be killing his own desires. Agnès is fed a meat pie. "How does it taste"? sings her husband. She understands the horrible truth. "I shall never, never, never get the taste out of my mouth" she sings, her voice reaching heights of horror, her lines once again stretching out in extended wailing.

Mehta appears as an Angel, surrounded by other angels who had also appeared as Marie and John, Agnès's sister and brother-in-law, now supposedly dead. Victoria Simmonds and Alan Clayton sang the roles. The Boy is now a protagonist in a painting, no longer man but immortalized as a work of art. Just as he had paiinted a woman falling, suspended in mid-air, Hannigan mounts the stairs at the side of the stage and disappears, followed by a group of retainers moving in slow motion. We don't need to see her fall. We already know. "Art" has become "life".

I'm not generally a fan of Katie Mitchell, but her directing in this was very perceptive. She and her designers Vicki Mortimer and Jon Clark have made split level sets something of a signature, but in Written on Skin the style works well with the meaning. Most of the action takes place, claustrophobically, in one room. The other rooms on other levels show the world that goes on outside the trapped manse. Perhaps the Boy is a quintessential Artist, who consciously enters other worlds when he creates a work of art ? He leaves his street clothes behind when he enters the Protectors's realm. Later, he's dressed by attendants so he can become The Angel. Perhaps it's a subtle reference to the relationship between artist and patron, as well as to the relationship between art and artist.

Written on Skin is only Benjamin's second opera. His first, Into the Little Hill, also to texts by Martin Crimp. was a highly condensed chamber opera about which I've written extensively. Read more HERE. Since Benjamin was hitherto a miniaturist, who worked slowly because he took such meticulous care, I was concerned how he'd write a full scale opera for a large house like the Royal Opera House and the seven other houses in which it is touring, I needn't have worried. Working with Martin Crimp seems to have stimulated Benjamin to new levels of creativity. Although Written on Skin is stylized and abstract, it is inherently dramatic on its own terms. Dare I say it, but I do feel that this will be one of the defining operas of the early 21st century, because it is so visionary.

George Benjamin's Written on Skin will be broadcast (audio only) on BBC Radio 3 on 22nd June.

Anne Ozorio