'I'm still interested in ways in which the imaginative side of theatre brushes up against reality,' says Yarker. In Bingo, three librarians suspect that they are not human at all, but robots, and so embark on a scientific test of their emotions, memories and reflexes. 'Their journey leads them to a bingo-machine which turns itself on and with each number called, randomly echoes back a saying in a God-like voice which refers to one of the three characters.'
Virtual reality is also a feature of the show, though of a low-tech kind. The performers find some old breakfast cereal boxes which, on their heads, lead them into a strange and beautiful virtual world which the audience can't see. It creates a reverse dramatic irony on stage, with performers thinking they're feeding handfuls of grass to a cow and the audience seeing them feeding a bit of crumpled up paper to a chair. 'Theatre is about creating virtual reality in a way,' claims Yarker. 'It's about creating a 3-D world on stage, with a certain interaction between the performers and the audience. In virtual reality, audience intervention is only available if somebody's programmed it in.'
BAC, 176 Lavender Hill, SW11 (071-223 2223) to 19 June