At 85, Merce Cunningham made a rare break with tradition last night, not only personally introducing his current London season, but letting us witness the odd little ritual that precedes every performance of his new work Split Sides. As its title suggests this is a dance choreographed in two halves, each of which can be accompanied by one of two scores, two backdrops, and two designs for costume and lighting. Cunningham has allowed for 32 permutations in all, and every night dice are thrown in order to determine which combination the audience will see.
This elaborate game of chance might look like a stunt - especially when attached to Cunningham's surprise choice of the bands Radiohead and Sigur Rós to provide his double score. But as soon as we see the dancers poised against the rainbow wash of Catherine Yass's backdrop - a neon city glimpsed through a blurred windscreen - and hear the dripped sound patterns of Radiohead's opening section, we can't imagine the work any other way.
Both scores sound better than they actually are by association with the choreography but even so the fit between dance and music is sometimes uncanny. Radiohead's favoured mix of vocal babble and static acquires an urgent, urban resonance when it backs Cunningham's most densely angled moves. Later when it morphs into a section of quiet drones, it builds to a rhapsodic intensity as two dancers tilt through a duet so intimate and spacious it's as if they're dancing alone on the roof of the world.
Midway through, Yass's colours give way to the black and white opacity of Robert Heishman's backdrop and at this exact point the twinkling oscillation of Sigur Ros's percussion sounds like the stars coming out. Eerily too the music seems an exact aural equivalent of the dancers' delicately spun leaps. None of this is planned yet the coincidences are vivid, acute. Like the best of Cunningham's work, Split Sides inspires us to become inventive collaborators in its poetry.
But there's a human scale to the work too as the 1965 classic How to Pass, Kick, Fall and Run delivers. The "score" for this piece is a string of stories, written by John Cage, and delivered with charm by David Vaughan and Cunningham himself. The showmanship could carry the piece, alone, but the playful choreography radiates a mischief that's vintage Merce.
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