DOUGLAS Maxwell's coming-of-age as a playwright has been a long, public business, not without its ups and downs. But now, with this great new monologue for Johnny McKnight's Random Accomplice company, Maxwell has made his breakthrough, producing a 90-minute text of such sustained brilliance, in its effort to confront some of the deepest problems facing our society, that it sometimes threatens to take the breath away.

The speaker is Miss Margaret Anne Brodie, a retired Scottish schoolteacher in London with a drink problem, and a lifetime of classroom experience. Asked to do some emergency supply teaching, she is enraged to discover that a traumatised and mute Somali girl who has just joined her class is to be subjected by "community leaders" to a terrifying exorcism in front of the other children.

Something about the situation, and about the compelling presence of the child herself, drives Miss Brodie into a vortex of passion and memory which she cannot control, as she remembers a youth destroyed by her own highly religious and abusive father; and what looks initially like a familiar attack on "political correctness" begins to shade into something much darker, more challenging, and finally more violent.

In the course of this fierce solo drama, performed by Joanna Tope and with an intensity, an allure, and a technical brilliance that is beyond praise, no aspect of victim-culture in our society – or the minefield of competing agonies it has exposed – escapes Maxwell's gaze.

McKnight uses Miss Brodie's ambiguous position as an abused middle-class woman, and a self-critical middle-class Scot, to demonstrate time and again how millions in the west are caught forever between the roles of oppressor and oppressed. In the end, Miss Brodie's response is to absorb Rosie's silence, and become mute.

But not before she has given us a story never to be forgotten; and a series of questions which are all the more worth asking, precisely because they have no answers.