DANCE / Dream genie: DANCE: Judith Mackrell on Wim Vandekeybus and Ultima Vez at the South Bank

How do you reconcile the fact that Wim Vandekeybus's new work ranks him as one of the most interesting creators of stage imagery around, while, as a maker of dance, it shows him stuck in a groove that's not only wearisomely repetitive but even faintly tacky?

Mountains Made of Barking is a kind of nightmare-in- performance; an 80-minute work which emulates the leaps of logic and the unfathomable intensities of dream time. Even its opening sequence leaves your flesh and imagination crawling. Five women creep from under a cloth and begin a frenzied, wheeling dance. As dissonant violins wail and drone, their tangled tresses fly around their heads - only gradually do you realise that these leaping furies have no faces and that their features are covered by thick, matted hair.

What dramatises the work's leap into uncharted territory is the fact that its lead performer, Said Gharbi, is blind. As we watch him navigating (very skilfully) through violent noise and crashing activity, we feel his dangers and uncertainties peculiarly on our nerves.

The threat of his confusion also emphasises the drastic changes which take place on stage. At times, it's a place of dark shadows, the muttering dancers shifting nervily around the space. At times, it transforms to a bizarre nightclub where a spivvy singer chants in incomprehensible German and the dancers gyrate in forced hilarity. Most radically, it empties to focus on snatches of film that are projected on to the back wall.

Here perhaps the work achieves its most surreal effects. Some are technically astounding, like the tracking shot which shows a horse and cart apparently riding up to the back of the stage through a painted landscape. Some are sickening, like the long sequence which mixes blood dripping from a decapitated chicken with the amplified sounds of scuttling beetles, and a man running with nowhere to go.

Somehow these images connect with live action. One dancer narrates the story of a couple whose wedding feast is visited by thousands of dead souls thirsting to drink their blood. Their terror is compounded by the dancer's own fear and disgust as blind Gharbi shuffles at her feet, trying to clutch at her knees. Behind her lurks the nightclub singer whose suit is now half-covered in animal fur.

In so many ways, this piece touches on our primitive imaginings. It's such a waste that, sandwiched into it, are passages of truly mundane dance. One exception, a sequence where the dancers slither round the stage like wounded reptiles, occasionally rearing up with shocking suddenness, shows what Vandekeybus can do when his imagination is feeding his steps. But the rest is a display of the whipping turns and lurching falls that have long been Vandekeybus's stock-in- trade.

Not only is this dancing stale and irrelevant, it also has a nasty tendency to parade its women as pretty victims. Though they kick and crash along with the boys, they're largely on the receiving end of the aggression. And with their little girly dresses, their restless wriggles and flouncing walks, they appear more like tame rock video princesses than the inhabitants of dark and dangerous dreams.