It's not that unusual for choreographers to invite musicians on to the stage, letting them occupy a discreet share of the dancers' space rather than consigning them to the pit. But in Diabelli, Twyla Tharp's setting of Beethoven's Diabelli Variations, the relationship between her 10 dancers and pianist Nikolai Demidenko is special.
Demidenko is, of course, a celebrated artist and his playing is never just an accompaniment to Tharp's steps. Though he sits at the back of the stage, with the dancers occupying the space in front, his big square body is as eloquent a presence as theirs, while the buoyant clarity of his playing is as sharp to our senses as the choreography. His powerful, muscular touch gives an impassioned scale to the sound yet he pays such luminous regard to details of phrasing that Beethoven's 33 variations on Diabelli's little waltz sound as if they've come new-minted from under his fingers.
It's the hour-long score itself that also makes this dance event unique. For Tharp has challenged herself to keep pace with one of the most flamboyantly demanding piano works Beethoven wrote. Less ambitious choreographers might wilt at the challenge. But when Tharp rises to it (as she does for quite a lot of the time) she creates a fascinating double perspective on the music. With her and Demidenko simultaneously letting loose their imaginations we see the music separating into two worlds, sometimes colliding and sometimes running mysteriously parallel.
As Beethoven shakes his little theme into hundreds of different rhythmic and dynamic patterns, so does Tharp. As Beethoven parodies forms and manners, so does Tharp. She colours her own material with jazz, high camp and tender sex, creating some of the best dance of her recent career.
It's wittily and elegantly performed and the event nearly rises to a triumph. But there are odd passages where Tharp's invention falls slack, and more worryingly, passages that run so counter to the dramatic pulse of Demidenko's playing that they seem an arrogant intrusion. The effect jolts dance and music lovers equally - a shame since Diabelli has such special potential to pleasure us all.
