Dance: Ocean, The Roundhouse

Although Merce Cunningham's largest work is named Ocean, its theatre plan is like the concentric ripples of a stone dropped into a pool. The dancers are in the middle, surrounded by the audience, who are surrounded by 150 musicians from the Guildhall School of Music and Drama. As you watch these extraordinary, complex dances, sound laps and gurgles around you.

This is the grand opening for this year's Dance Umbrella, and it shows off 360° of the reopened Roundhouse. It's a huge, handsome building with a central ring of slender iron pillars supporting a pointed roof.

With John Cage, Cunningham developed dance that was made separately from its music - the design, sound and steps of a Cunningham production often come together at the first showing. Ocean was the last work he planned with Cage, who died in 1992. It was completed two years later, with music by Andrew Culver.

These Roundhouse performances are the first time Cunningham's company has had the full 150 musicians dreamt up by Cage. Marsha Skinner dresses the dancers in body tights - blues, golds, greens - with shifting, dappled lighting. David Tudor adds an electronic score, stylised noise turning into gulls or barking sea lions.

Ocean starts with one man, moving fast, skidding to a halt.On one foot, Daniel Squire tilts and arches his body, limbs and torso into new poses. He throws his weight suddenly to the side, or turns on the spot, reaching out to the whole house.

Cunningham will set arms, legs, and torso moving to different rhythms. Then he asks the dancer to do all that within a single balance, or while hurtling through space. One woman sprints and flings herself at a man - who doesn't turn to catch her until after she has taken off. A whole flock of dancers keep changing direction, feet quick and lively, never peeking to see where they're headed.

This 90-minute work isn't Cunningham at his most expansive, or his most accessible, and I found myself tuning out at times. Yet this cooler, drier work will suddenly change and ripple. Breathtaking movements keep drawing you back into its shifting landscape.

Until 24 September. Box office 08703 891 846