Les Sept Planches de la Ruse, Barbican Theatre, London

The "sept planches" are the seven pieces of the Chinese game Tangram, a set of geometrical shapes that can be arranged into different patterns. This show uses giant versions of the pieces – big enough for performers to clamber up, around and inside, holding balances or sliding down angles. Shapes unfold with peaceful grace and dashes of comedy.

Showing as part of the London International Mime Festival, Les Sept Planches was created by Aurélian Bory, director of French performance company Compagnie 111. For this work, he has cast actors from the Beijing Opera, who are used to singing, acrobatics and dancing, often simultaneously.

The pieces begin slotted together in a single block. A woman perches on its edge, playing a traditional stringed instrument. Around her, the acrobats start pushing at the blocks, which slide gently into new patterns. Eventually, finding the musician in the way, they slide her along too; with a frantic scrape of the bow as she goes round a corner.

Bory finds plenty of humour in his geometry. When the sliding shapes leave a gap, a performer slides into it and the shapes close over her. A minute later, as the large block breaks up, one of the pieces toddles away by itself. The comedy adds variety to a gentle show and emphasises the human presence.

Upended, the triangles and squares become steep slopes. The acrobats sprint to the top, where their weight overbalances the block, tipping it into a new pose. There's little sound as the blocks slip into place, no jerks as the pattern moves. The blocks can even fall slowly. A man stands on a triangular block as the supporting pieces are pulled from under him. You're waiting for the crash, but it never comes: instead of plummeting, it glides steadily down, perfectly controlled.

In another scene, three women keep singing, in Chinese Opera style, leaning against blocks. As the acrobats move the pieces, the singers slide down to the floor, or are pushed back onto their feet – still singing. Groups chase each other round and round the same block, or manage to climb inside it.

Throughout, Les Sept Planches de la Ruse demands an exact sense of space and balance from its performers. It has some brilliant acrobatic flashes, too: a dancer sprinting up a vertical wall, or cartwheeling off a high surface. Sometimes the acrobats are disconcerted by the way their walls and floors tilt or vanish; more often, they accept the changing landscape with deadpan stoicism.