Dance; Herve Robbe / Richard Deacon Dance Umbrella 95 Riverside Studios, London

Dance performances that depend on audience participation can often be their own worst enemies: a choreographer may be able to make an informed guess at how his or her public will respond to being made part of the show, but the risk of causing alienation still looms large. Likewise, if audiences are becoming more wary of such performances, it could be because their inclusion is rarely entirely unexploitative.

It is surprising, then, that so many people turned up for the Dance Umbrella festival event entitled Factory - a collaborative work created by the French choreographer Herve Robbe and the British sculptor Richard Deacon - given that most of them must have been aware that Robbe and Deacon had devised a show in which the public were to play a major role. Then again, perhaps I'm not reading this correctly: maybe there are lots of people who relish the idea of joining in the stage action - it's just that I've yet to meet them.

But if any one show could convert those dancegoers less inclined to lend themselves to live performance, it would be Factory. Seldom has audience participation seemed such fun and so total. With its seating removed, Riverside's cavernous Studio 1 served as a suitably industrial environment for Deacon's metal tracks and grids, pulleys and hanging rods, and a massive piece of overhead machinery - a sort of corset with a waffle iron base - which slowly filled with air and light as it descended. But as if to bring human scale and organic forms to his machine room, Deacon adds a number of gently curved wooden boxes which the dancers drag, push and stack, or against which they mould their bodies.

Entering the space you found yourself in the midst of the evening shift, caught up on a free-floating production line worked by the six dancers (three men, three women). How well you could see the performers depended on where you stood - or crouched or turned. Often the frustration at being last on the scene and thus unable to see through the throng, was countered by the fact that you were then liable to notice another patch of activity starting up elsewhere. These overlapping but different sequences had the audience circumambulating like lost but curious sheep. Much of the choreography was flaccid and dull, yet it looped around the site with ambient ease, even when the dancers had to press through the crowd with dogged determination in order to claim another area of the shop floor.

As the work progressed, audience, dancers and setting moved more and more harmoniously and functionally around each other, becoming a single triangle of forces. And if you had started the evening as an observer on the outskirts, you now felt inexorably drawn in: as an intrinsic part of the factory's geography, you forgot about looking at its map from afar.

n The Dance Umbrella Festival runs until 11 Nov. Booking: 0181-741 2255