Cracking the whip for S&M, John Keates has created a piece of theatre that succeeds in both getting under the skin of consensual sexual cruelty and revealing its nature to its audience.

The irony is that, for all that this is an adults-only show, all the sex and eroticism in the production is in the writing and not the performances of Keates and Anna Brook, as lovers Steve and Emily. They perform fully clothed in T-shirts and jeans throughout, and their lines are delivered deadpan like stage directions, so that any revealing clothing, nudity or mutilation is all in the audience’s imagination.

And the imagination is what the depths of their depicted depravity is all about. The pain and its release are all about trust between two adults, about heightening and lengthening the enjoyment of the sexual act. It is about how sex becomes a ritual act in itself. Revealingly, the greatest pain inflicted in the piece is purely emotional, as Steve describes a fictitious affair to Emily while they are making love.

This is an honest and open account of a difficult subject, but in keeping such a sanitary distance from the messy part of S&M, it doesn’t satisfy as it might in theatrical terms.