My heart is bursting with the wordless song that filled a dark and cavernous brick vault, with such warmth and such friendship that I conclude must be unique to the art of modern opera. A hymn to the labors of sisterhood and the collective efforts of love, The Swarm sits somewhere between a choral concert with physical movement sequences, and a bare stage modern opera without a story but a clear emotional ark.

It’s also an artistic natural history, using the language of bees and the swarming patterns of their queen and workers to create a structure for performance. Heloise Tunstall-Behrens has created a sound vision that brings each tone from the personality of each voice. Created are multi-part harmonies which ring with the history of Philip Glass and Arvo Pärt and soul, but form something quite beautifully new by structuring their song around the activity of worker bees in a hive. What sounds like a series of repeated consonants and vowels in fact form a poem about the swarm’s journey to a garden, working up to a spiritual climax. It’s a very beautiful thing.

There is no weak link in this chorus. Each voice is used to its full advantage, bringing together the alto, mezzo, full lyric, and light heady soprano sounds to find unity in difference. The whole group was never for one moment off pitch throughout soaring acapella sequences with tricky, close knit harmonies. And they were always in time when an electronic soundscape by Auclair kicked in.

In the beginning, the stage is in darkness and the queen bee asks her onlookers to hum and warm her worker bees into action. It is lovely to use our voices – just a little – to instigate the sound of much more glorious ones. I would have liked them to take this fulfilling theme of gentle audience interaction and engage us with eye contact or physical closeness. In such an intimate and sparse playing space, it felt odd that the women I was watching didn’t feel emotionally closer and more connected to me.

There are moments too when the physical sequences were too loosely choreographed and not quite cleanly timed. I think director Roswitha Gerlitz could have been braver, trusting in the voices more, and had moments of stillness where we could just listen. Parts seemed a little bit like drama school warm ups or playground games. Nonetheless, the story of collective effort by The Quorum was pleasing to watch as we experienced their sound.

There’s something very beautiful about seeing different women’s bodies and movements in the same dress and makeup – one lady is pregnant, another has messy ash blonde hair; one has freckles in abandon over her cheeks, and one has black natural hair plaited back neatly. The gold pattern of smudges on each girl’s face gave an aura of bee-like nature and ancient symbolism to the choir. The honey smelling incense and intense lighting in the vault helped with this rich sense of pre-history and unconscious wisdom.

The Swarm played at Vault Festival until 12 February 2017. For more information about the company The Quorum, click here.