Ashton's Romeo and Juliet, London Coliseum

Like planets crossing in the skies, light years apart, but by some ocular illusion coinciding, this conjunction of the two most thrilling young Bolshoi stars in the world and Frederick Ashton’s rarely staged Romeo and Juliet really must be seen. Natalia Osipova and Ivan Vasiliev are real-life lovers as well as phenomenal work colleagues and passionate actors. The freshness of youth, the unhindered outpouring of emotion, the finish of their dancing, and their direct stage personalities enrich to bursting a chamber-sized telling of the tragedy that's refreshingly intimate by comparison with the more popular blockbuster versions.

Ashton’s version predates the landmark Bolshoi visit of 1956 with their powerhouse version, which altered everything. His, made for the Royal Danish Ballet’s small theatre and their delicate, precise dancing style, is a baroque cantata in comparison to the great ensemble ballets to Prokofiev’s score that would sweep Europe after the Bolshoi trip.

Without preconceptions, he clipped the music down to fit his vision of something distilled directly from Shakespeare’s list of characters, with very spare group ensembles - it aims to be lyrical verse, not dramatic symbolism like the Bolshoi's Lavrovsky version, nor naturalistic dance prose like Kenneth MacMillan's, nor socio-political commentary, like Rudolf Nureyev's. It’s a tragedy behind closed doors.

But there was no polite restraint in Osipova and Vasiliev last night, the official opening of this week's run at the London Coliseum. He, the Bolshoi’s most lionised new Spartacus, looked initially cramped by Romeo’s opening solo - as economically graceful as a galliard, with much play with a fluttering cape. But then the curly-haired lad with wings on his heels unleashed arrow-fast jumps, burnished the dancing with Bolshoi macho (not equalled by his sword fighting, though).

And he was so grave and careful with his girl - there was an anxious fatalism about his performance which indicated that this Romeo was slightly better attuned to the potential for disaster than Juliet. This sort of sensitive tuning is rare in some of the bigger-scale dancers, and it sets Vasiliev apart as an artist potentially to live through emotional dilemmas with, rather than just gawp at for his physical dynamism.

Osipova, with her gamine black crop and alabaster skin, is a world-beater too. Those few lucky enough to get into Bolshoi performances in London have seen the laughter in her dancing, the sunbeams in her leaps and spins. Again, this is not that kind of thing. Ashton’s Juliet has a whirring, beating quality that’s all about iridescent detail, not about the cosmic flight and rocketing speed that Osipova’s uniquely capable of. But she’s turned that physical bounty into sheer life force in her characterising. (Osipova pictured right with Marguerite Porter as her mother.)

She bounded with such happiness into the ball, succumbed with such giddy excitement to the blandishments of the masked Romeo, that you almost wanted to tug the child back, warn her. And this is acutely Shakespearean.

The Balcony Scene is scaled down - they stand close together touching each other, no hurtling about the stage as they do in the MacMillan - but no scaling down at all in young unrestrained rapture in these two. It’s a deeply touching pas de deux, with constantly evolving variations on embracing arms, closely winding, or spraying out in triumph, unorthodox and almost contemporary, particularly for the girl. Overall one can see why companies go for bigger, more impactful R&Js, with shorter mime scenes and striking ensembles the measure of the music, yet these softer tints gleam touchingly with such performers as these two.

Graham Bond and the ENB Orchestra provided a brisk, matter-of-fact musical performance, so I didn’t mind losing so much of the music as to keep the action to well under two hours (plus interval). Though Ashton later restored some, and made ensemble dances for the 1985 London Festival Ballet production he did with Peter Schaufuss, then LFB artistic director and star, Schaufuss has reverted to the sparer bones of the 1955 original. The one dance it hurts my memory not to see here is the pre-wedding wake-up Mandolin Dance outside Juliet’s room while she lay in her drugged stupor, the carefree entertainers underscoring the pain of the tragic misunderstandings about to take place.

More painful in Schaufuss's production is that the stage design lacks any dimensional integrity, simply shooting colour washes or black-and-white photo projections of old Italy over the back. Though mostly suitable images (apart from the nauseating red rose petals when the lovers meet - I ask you), the sense of place is much subverted by the baffling columnar neon-lightboxes either side, more contemporary hotel lobby than a setting for a medieval love story. Ashton's work is too much a period piece to look comfortable so stripped of place and time.

While one’s eyes can’t easily be lured away from the leading pair, Schaufuss thoughtfully provides a new young Royal Danish Ballet talent, Alban Lendorf, as Mercutio, tall, affable and well built, with finely timed feet. We also see an amazing bleached-blond Goth of a Tybalt from another Dane, Johan Christensen (pictured left, with Robin Bernardet as Benvolio), in slashed black doublet and hose - his death roll down the stairs looked spectacularly bruising.

And last night, a special gala show for the Dancer for Cancer Trust, there were extra characters on stage, the senior generation of authority figures played by a considerable galaxy of former English ballet stars, Schaufuss’s colleagues of old. Marguerite Porter, Stephen Jeffries, Donald MacLeary, the two Waynes, Eagling and Sleep (still, at 62, slappably saucy and spinning like a top). Lynn Seymour, promised as Lady Montague, failed to materialise.

Schaufuss himself played Friar Laurence. Forty years ago he made his dancing debut on the Coliseum stage with Festival Ballet. His parents were the original cast for Ashton’s Romeo and Juliet, as Juliet and Mercutio. This week his daughter Tara plays Livia, Mercutio’s girlfriend. Her mother, Janette Mulligan, was an LFB dancer too. Many historic and sentimental reasons exist for this show - but the essential reason is that there are two performances at the heart of such unaffected and affecting sweetness.

• Ashton's Romeo and Juliet is performed by the Peter Schaufuss Ballet at the London Coliseum till Sunday
• Read theartsdesk interview special with Natalia Osipova, Ivan Vasiliev and Peter Schaufuss
• Also on theartsdesk:'Romeo and Juliet in Ballet and Opera' - a survey

Watch a young Johan Kobborg and Michelle Larsen with the Royal Danish Ballet in the Ashton R&J Bedroom pas de deux