ma, QEH, London SE1<br/>Bamboo Dream, Barbican, London EC2

Top of the world, ma. (Well, pretty close at least)

When a top nob of the South Bank gets up before a packed house and says that what we are about to see "is obviously going to have a huge impact around the world", you wonder if that isn't a little presumptious. Akram Khan's latest creation, ma, only his second full-length work, arrives staggering under a weight of expectation. Inspired by Arundhati Roy's essays about farmers in India being evicted from their land and using spoken text by the writer Hanif Kureishi, the new piece appeared to hold out the promise of some new form of agitprop, dance theatre with a message that would spark political awareness wherever it played.

When a top nob of the South Bank gets up before a packed house and says that what we are about to see "is obviously going to have a huge impact around the world", you wonder if that isn't a little presumptious. Akram Khan's latest creation, ma, only his second full-length work, arrives staggering under a weight of expectation. Inspired by Arundhati Roy's essays about farmers in India being evicted from their land and using spoken text by the writer Hanif Kureishi, the new piece appeared to hold out the promise of some new form of agitprop, dance theatre with a message that would spark political awareness wherever it played.

But it isn't like that. Though Khan certainly breaks new ground in ma (Hindi for both "mother" and "earth"), he shies away from narrative, ending up with the usual if in this case brilliantly worked abstraction that Western contemporary dance has become. "Let me tell you a story..." says Khan promisingly at pivotal moments, but each time the story peters out. First, Khan relates a childhood memory, of hanging from a tree to let ideas fall out of his head. It's a theme echoed in the many upside-down poses, including, in the opening moments, the vocalist Faheem Mazhar hanging from his heels while singing a ravishing lament.

The second story is relayed by a pair of women who up-end themselves to resemble saplings while they bicker over the details of a fable. While the episode is touching and humorous, it feels like a diversion, not a development of a theme.

Which is odd given Khan's devotion to kathak, the north Indian classical dance form in which movement is inseparable from story-telling. Formally, kathak's spirit infuses everything in ma. Its flat, stamping feet, its whirring arms, its speed, mesh seamlessly with modern handsprings, barrel rolls and off-centre lurches to forge a mercurial style that can send a body careening across space like a skimmed pebble. As always, Khan's own contribution is riveting, but he's generous, too, choosing fellow dancers quite as sleek and fast.

Given the work's beauty - lighting that goes from moonlit paddy field to noonday glare; a score that abuts curling Sufi melodies with fabulous Indian tabla, and the sheer mathematical rigour of the dance - it might seem churlish to complain that I did not go home fired up to change the world. If Khan really wants to make placard art, or even art that asks questions, he must lose his modernist's fear of narrative, get to grips with his story-telling past.

By coincidence, Bamboo Dream, the new work brought to the BITE festival from Taiwan's premier dance company, Cloud Gate, also has an eco theme. It too plays with humour, though with brasher results. At the start, though, it seems to be in deadly earnest. A bamboo grove, 20ft high, presents a fretwork through which the dancers drift, trance-like in their Tai Chi moves, impeccably serene. "Spring" and "Summer" bring a more dynamic style, including jumps that seem to rise resistingly and hang in the air. "Snow" brings a pretty sprinkling of polystyrene flakes, and then something weird happens. We enter Pina Bausch territory. The women go all shampoo-advert, swinging loose tresses in the breeze generated by a barrage of electric fans. Then they give us the Marilyn treatment, splaying their skirts as the men lie at their feet directing the fans at their knickers. Is this an in-joke about Taiwan's home-electricals exports? It certainly feels as if the rug has been pulled. By the time the stage crew arrives to remove the (obvious to us now) plastic bamboo canes from their metal slots, the whole thing is shown to be a sham, poetry and all.

jenny.gilbert@independent.co.uk

'ma': QEH, London SE1 (08703 800 400), tonight. 'Bamboo Dream': Barbican, London EC2 (0845 120 7550), tonight