A woman staggers into the Ladies’ Powder Room at the Queen Victoria Building with red eyes. She checks to see if anyone is occupying each of the three stalls before allowing a sob to escape. She washes her face at a basin and uses the mirror to inspect bruises on her shoulder and wrist, lifting her shirt up to examine another on her back. Staring into the mirror, she delivers a haunting, visceral rendition of When I am Laid in Earth, Dido’s Lament from Purcell’s opera Dido and Aeneas, as she counts out pills from a bottle.

It is an excruciatingly intimate scene, in the safe, private and female space of the women’s bathroom – and it all happens inches in front of me, my knee wedged under the basin next to hers.

A deliberate subversion of the “witches, bitches and breeches” roles female opera singers are so often required to play, Clemence Williams’ site-specific pasticcio Chamber Pot Opera tells the story of three strangers whose lives briefly intersect in the Ladies Powder Room. The first woman, sung by Sally Alrich-Smythe, flees to the privacy of a stall as another woman (Jessica Westcott) enters, singing a boisterous L’amour est un oiseau...