Dance: Sacred Monsters, Sadlers Wells, London

Vanity, vanity, all is vanity

In a week already thick with major dance events in the capital - the legendary Merce Cunningham Company launching Dance Umbrella at the Roundhouse, the finals of the Place Prize in full swing across town - it's a rogue one-off that has hogged the public imagination. Sylvie Guillem's name alone would have guaranteed a stampede to Sadler's Wells, as would Akram Khan's. Put the Parisian ballet superstar and the London-born kathak star together on stage and the prospect has had dance fans practically fainting with anticipation.

But, oh dear, what a let-down. Sacred Monsters is the title of the show they've put together, and it's proved a sight more apt than either of them intended. The monsters it's supposed to refer to are the slave-drivers of the stars' careers: on the one hand, the pressure of having to live up to their own high standards; on the other, the rigid and restricting discipline of their respective classical traditions. Khan was thinking too of the twin poles of Indian thought, with the masculine, disciplined way of doing things represented by the god Shiva, set against the questioning, rebellious model of Krishna. So far, so simple: a case of yin and yang, hard and soft, tradition versus innovation, structure versus the unfettered flight of the creative imagination. If they'd stuck with this idea, each dancing an academic solo, then a free-form one, showing us where each is coming from and where they're going next, it would have made a tight and appealing little package.

Instead, the monster we're presented with is the monster of vanity, a muddle of psychobabble, self-reference and fake confessional, and I use the word fake advisedly. The substance of Sacred Monsters may not be factually untrue, but it's coyly delivered in speech that purports to be spontaneous and is too obviously the chiselled construct of dramaturge Guy Cools, the latest addition to the multi-pack of designers and consultants that a trendy dance work now requires. When dancers open their mouths on stage they have to have a very good reason. Their medium is dance, after all - they're not trained to sing or talk. In fessing up to a large audience about diary-private matters - Sylvie worries that she's no longer "émerveillée" by the wonders in the world, Akram recounts how he once considered black hairspray to disguise his bald patch - they are essentially saying, look at me, not at my dancing. Look at what a complex, tortured individual I've become.

A couple of bouts of good, tough choreography could have saved this soggy chat-fest, but there's little on display. The worst comes first, in an interminable solo for Guillem by Lin Hwai Min in which she doodles around the stage and wriggles on the floor, showing off her famous high extension in meaningless kicks and splits to a gloomy troubadour song delivered by a woman in a sack dress over a violin drone (five musicians are up on stage as well). Previously I'd have sworn I'd be transfixed by Guillem's extraordinary body even if she was hanging out her weekly wash. I now know that even the greatest artists need great material. This is so far off the mark that it's embarrassing.

Khan comes off better in his solo, devised for him by Gauri Sharma Tripathi. It's an uneven match not only because it boasts a structure and a style, and the ravishing melismatic Indian singing of Faheem Mazhar, but it's utterly traditional, and though Khan plays this down by dressing in a T-shirt, the sequence has the grand eloquence of kathak with its shivering footwork, arrowed turns and lushly florid arms. Yet even this small piece of perfection gets tampered with, as Khan begins and ends with a horribly misjudged pretence that he's trying, and failing, to resist the tug of tradition. Extending his arms stiffly and looking distressed, I only saw a client in a kinesiology test coming up positive for wheat allergy.

The stage setting, by Shizuka Hariu (they've assembled a thoroughly exotic bunch), is a striking white Artex-covered cave with a slash in it. The lighting, by Mikki Kunttu (a Finn, if you're wondering), is modishly flat and glamorous in grey. But even these meagre house-points are cancelled out by the sheer banality of the stars' dances together. The first, in which Sylvie takes the lead, is based on the most elementary student exercise in contact improvisation: let's join hands and you do what I do, OK? They snaky-snaky their arms. A nudge of Sylvie's hips sends Akram off-balance. He responds with a pretend headbutt. It goes on, and on.

For me the sole point of interest is the extent to which it's Guillem with her lean and loosely structured body who looks awkward and gawky in this ill-defined play-dancing while the more compact Khan looks almost at home, if grossly under-stretched. Had I paid £35-plus for my ticket I'd have wanted my money back. We all accept that it's tough at the top. But asking your audience for sympathy, still worse, to witness your therapy sessions, will always be in very poor taste.

Jenny.gilbert@independent.co.uk