Diversions, The Place, London<br/>La Cit&eacute; RADIEUSE, Dome, Brighton

Speech isn't rare in contemporary dance, but it is unusual to see it mixed with such disciplined moves, as it is here by the national troupe of Wales. In Chase the Glowing Hours with Flying Feet, set to Bach, Hélène Blackburn lays great stress on lines and angles. Diversions isn't a classical company, and they could make the movement more sculptural. But these steps are projected cleanly and with assurance. Blackburn has a sense of stage space, and she makes these dancers look good.

In between movements, they speak into microphones, or recite the alphabet with mime gestures. These spoken sections could be irritating, but they're done with animation. It's an bright, energetic piece, and it suits the company.

In La Cité Radieuse, by the Ballet National de Marseille, you can hardly see the dancing for the theory. In his third dance/architecture collaboration, Frédéric Flamand sets out to evoke changing public space, virtual reality, advertising and the body. His dancers wheel mesh screens around, ducking behind projections.

This piece is named after a Marseille landmark, the apartment block created by Le Corbusier. La Cité Radieuse, the ballet, has been shaped by another architect, Dominque Perrault, who designed the metal screens that dominate the piece. A man lies inside a box of screens. A film projection shows him from above, suggesting da Vinci's Vitruvian man. Once the dancers get up, however, Flamand can't find enough for them to do.

The choreography is active but blank, keeping the dancers moving without telling us much about them. The screens and film clips overshadow the movement. When the screens are pushed back for a series of pure dances, interest immediately flags.

Film provides the most interesting aspects of La Cité Radieuse. A chair is projected on to one screen, its outline so fierce that for a moment you can't see if it's real or virtual.

Yet the piece is incoherent. Perhaps Flamand means it to be; his programme notes are full of discussions of utopia, of technology, of intermediate places like airports and shopping malls. Flamand may have ideas about the modern city, but he doesn't animate them onstage.