Unlike the mysterious beguiler of Shakespeare's song lyric "Who Is Sylvia?" Sir Frederick Ashton knew just who Sylvia was. In his ballet she's one of the Goddess Diana's huntress nymphs, sworn to chastity, who encounters all sorts of adventures in an Arcadian world of ancient myth. Choreographed in l952, it was a tribute to and vehicle for Margot Fonteyn, then at her zenith. Wrote critic Clive Barnes, "the whole ballet is a garland presented to the ballerina by her choreographer". It was also perhaps an oblique homage to Petipa's three-act ballets, this being Ashton's second evening-length work following Cinderella. American Ballet Theatre in co-production with the Royal Ballet is presenting this full version.

Says Gillian Murphy who dances the title role: "It's challenging both from a technical and an acting point of view. Sylvia has to be strong and powerful in the beginning, feminine and vulnerable later. The choreography is really stunning, the music glorious, the costumes exquisite‹they're really made for a woman's body. Every single thing about it is exciting. I particularly enjoy the way Ashton interprets the music."

Its composer, Léo Delibes, who broke away from the more formal and humdrum ballet music of his time was hailed as the father of modern ballet music after composing Sylvia ou La Nymphe de Diane in 1876 for the Paris Opéra. Tchaikovsky said it inspired him to write Swan Lake and the ever-popular score has became the driving influence for several other choreographers, including, most notably, George Balanchine.

Artistic director Kevin McKenzie explains that he discovered Sylvia when going through the Royal Ballet's Ashton archive. "There was film footage which although incomplete was absolutely wonderful. I wondered why no one had thought of doing it." Indeed, the Royal Ballet was preparing for its Ashton centennial and was planning, despite difficulties due to lack of records, to revive it. Said McKenzie, "we have a good relationship with the Royal Ballet especially with our successful Ashton celebration, with La Fille mal gardée and other works of his in our repertory. We agreed to share responsibility for the set, [based on Robin and Christopher Ironside's original Second Empire-style designs], and the costumes have only been changed to use contemporary materials. Christopher Newton, who has staged it for us adapted the ballet into two acts without forfeiting its essential elements. He took out material from La Source that wasn't in the original score, omitted an intermission and inserted a musical pause‹and then the ballet continues."

The revival could not have happened without Newton, former dancer and ballet master, later 'artistic-cordinator' for the Royal. Says Newton, "It's a simple story‹in Ashton's description: 'boy loves girl, girl captured by bad man, girl restored to boy by god'‹that comes across so strongly in his choreography. It's all shown through the dance. There's virtually no mime." But he adds "Ashton was always very casual about recording his work and there were just people's memories to rely on, a murky film and a few clips from the all-important third-act pas de deux‹bits and pieces from galas, and an incomplete record of Nadia Nerina in the title role that concentrated on her dancing in close-up. For the revival I worked on the research for eighteen months before we even started."

Newton had joined the ballet at seventeen and danced in the original production. "Fortunately when it comes to choreography I have a photographic memory; I danced in Sylvia as a student in l953. In the corps de ballet I memorized my own and many other parts. I was always very aware of what other people on the stage were doing" Also he'd studied Benesh notation and kept his own private notes of the work. "Over the years I worked closely with Ashton especially after I became ballet master. Sylvia was something he wanted to do again and we talked a lot about it only three months before his death. His main concern was Act II." (At one point he'd put it into two acts and finally reduced it down to one.) "Since Ashton changed things all the time I've adapted a few small details for the dancers. One has to be flexible but keep the spirit of the thing".

Audiences may be puzzled by the two sprightly goats at the beginning of Act III, who with their playful pas de chats resemble the cats in Petipa's Sleeping Beauty. "They've always troubled me," laughs Newton. "They're meant to be sacrificed in the festival to Bacchus and because it's interrupted, they get spared. I thought of changing them to fauns or nymphs. But they need to be there if only to give the principals a rest before the big pas de deux, otherwise I think it would be a killer." McKenzie laughs them off too as Ashton's penchant for putting animals into his ballets like the chickens in Fille, (which also has a live donkey), Pépé the dog in A Wedding Bouquet, and of course, his anthropomorphized creatures in the film, The Tales of Beatrix Potter.

Now with a lot of painstaking work, Ashton's Sylvia, not seen in its originality for so long, is restored to glory and the ballerinas of ABT have a chance to wear that garland Ashton so fondly presented to Fonteyn long ago.