Iron, Traverse Theatre, Edinburgh

Murder meets mother-love in a steely domestic drama

It's not hard to see how Hollywood would cheapen the situation that's developed so truthfully in Iron, the new play by Rona Munro that gets the Traverse Theatre's festival programme off to a powerfully involving start. Feisty Fay murdered her husband with a kitchen knife and has served 15 years of a life sentence. Now, her 25-year-old daughter, Josie, a globe-trotting career girl who is unable to remember anything before the fateful day, makes her first visit to the prison. Will the encounter dislodge her memory block?

In a movie, the Josie character would begin to suspect that it's Fay who is the real victim, taking the rap to prevent her daughter from discovering the bleak truth about a violently abusive father. The young woman would then forfeit her own professional success in order to uncover the facts and to campaign tirelessly for a review of the case. Mother and daughter, consciousness duly raised, would join hands in sisterly solidarity. The result: liberation, both literal and metaphorical.

It's one of the many strengths of Munro's moving play that it floats the possibility of this scenario, only to reject it as a false hope that Josie must be persuaded to relinquish. There's an earthy Scots humour in much of the dialogue, but the piece aches with the feeling that this couple, who meet as awkwardly intimate strangers and gradually become the centre of the world for each other, are doomed to a future that will be as painfully truncated as their shared past.

True, their bond is only strengthened by the institutional prohibition on privacy and physical contact that Roxana Silbert's starkly designed production conveys in all its upsetting vigilance. Their relationship can't last, though, because of the couple's conflicting needs. Louise Ludgate's fine Josie lets you see, under the yuppie gloss, a rather lost and lonely woman who might well seek to shelve her own problems by making a round-the-clock mission of her mother. Fay, however, had wanted to live vicariously through a vibrant, socialising daughter, not through some single-issue crusader. Sandy McDade's superb performance shows you a gangly, avid stork of a woman, who piercingly pines for the pleasures of the outside world (the taste of hot chips; kissing a man with a moustache), but who is not prepared to re-achieve these amenities by traducing the memory of her loved and grievously missed husband.

Munro and McDade ensure that the heroine's loving self-sacrifice in rejecting Josie for her own good is not smudged with sentimentality. The cussed, erratic, angrily impulsive side of her that troubles the guards (Helen Lomax and Ged McKenna) remains on view. It's a mark of the play's scrupulous honesty that it leaves a slight question mark dangling over whether, without Josie, Fay will now be able to live with herself.

Venue 15: various times (2hrs 15mins), in rep to 24 August (0131 228 1404)