THEATRE / Burning issue: Dogspot - Nuffield, Southampton

White-faced, warily hunched, alternately sunk in hostile silence or screaming in her sleep, the adult actress Tilly Edwards gives a quite extraordinary performance as Mary, the traumatised 13-year-old in Dogspot, Claire Luckham's powerful new play. After her parents are dreadfully injured in a fire, Mary, refusing to speak or to go anywhere without her toy dog, is taken in by two unfamiliar aunts who have long been estranged from their burnt sister.

Mary, it gradually emerges, is not the only member of this clan who is leaving the unspeakable unspoken. 'In our family,' says Dove, the married, career-mother aunt, 'there are silences like suitcases' - a simile that might seem too studiedly poetic (conjuring up packed-away emotional baggage), were it not for its bleakly prosaic source. Their father was a travelling salesman, and, in both his absences and presence, was the cause of the blight afflicting the household.

You could argue that child abuse is the contemporary theatre's answer to the ancestral curse in Greek tragedy - and that, in opportunistic hands, it seems altogether too convenient: the dark secret that will explain everything handily waiting to be revealed. There's nothing remotely exploitative, though, about Luckham's scrupulous, insightful approach to the topic. Her focus is less on the abused young girl than on the effect of Mary's blurted- out, confused revelations on the aunts; their childhood experiences, now painfully brought back to mind, show that abuse need not be sexual.

Luckham's last play, The Choice, was a profoundly affecting study of a woman desperate for a child who discovers that she is pregnant with a Down's Syndrome baby. In Dogspot, too, what it is to be a mother is a potent theme.

Mary needs unconditional love, but is Dove, whose identification with her and obsessive desire to protect become almost deranged, the most suitable person to give it? Is the dried-up, childless aunt (Cherrith Mellor) correct in saying that mothering has been Dove's way of covering over the inner emptiness that is their inheritance? To a woman whose own children are now grown up and independent, and who so needs to redeem the awful family past, is Mary too much of a 'solution'?

Lisa Harrow's superb, unsparing performance as Dove keeps your sympathies rightly complicated. Moving fluently on its composite set between the often comic realism and the more poetically heightened passages, Patrick Sandford's production does handsome justice to the play. True, there are weaknesses (her relations' intermittent insensitivities to Mary seem point-makingly crass, the timescale melodramatically compressed), but this is a work that will go on nagging at the memory.

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