We read a lot these days about "grey power", the realisation that pensioners can swing elections. What few have noticed, at a time when youth is prized, is that in the theatre too the oldies are fighting back. The most popular plays in London are by writers such as Frayn, Bennett, Nichols and Plater, all of whom are technically eligible for bus passes. And further proof that creativity is not dimmed by age comes from Arnold Wesker's Denial, which deals with false memory syndrome.
Wesker himself is the victim not so much of repressed memories as of exaggerated nostalgia. In Britain, we prize so highly his early works - The Kitchen, Roots, Chips with Everything - that we tend to downgrade everything he has written since. One reason, I suspect, is that we favour obliqueness over Wesker's brand of emotional directness.
If I have any personal regret it is that Wesker now largely forswears the kind of choreographed action that characterised his early, autobiographical plays. No one can forget the lunch-hour pandemonium of The Kitchen or the night-time raid on the coke store in Chips with Everything. As Wesker once said in an interview, "The theatre is a place where one goes to see things happening." But, as he has increasingly focused on ideas or moral dilemmas, he has scaled down dramatic action.
Throughout his career, however, one subject has always dominated Wesker's thinking: family cohesiveness. As Tynan shrewdly noted in 1960, "His characters belong together, even when they are not on speaking terms with each other." And it is the attempt to dissolve the molten security of family that is the real subject of Denial.
In 21 scenes and 90 minutes, Wesker shows Jenny, whose marriage and career have broken down, accusing her father of raping her as a child; even her mother and grandfather have been complicit in persistent sexual abuse. Needless to say, the accusations come at the prompting of a therapist, Valerie, who is seeking the cause of Jenny's depression. But is she unlocking genuinely repressed memories or seeking a facile explanation for Jenny's problems?
The danger in a play on this theme is obvious: of lapsing into therapist-as-villain melodrama. But, with considerable dramatic cunning, Wesker largely avoids that trap. As played by Susan Tracy, Wesker's Valerie at first seems maternal, caring and indignant at the vilification she and fellow therapists have to endure. As she explains to a TV interviewer, she is the one who has seen "eight-year-olds with vaginas burst open by cycle pumps, young boys with gaping anuses, children who shud der at your touch". What she cannot forgive is violation of childhood trust.
But, as the play progresses, we see that Valerie, haunted by her experiences as a Cardiff social worker, seeks a catch-all solution to complex problems. In slowly shifting the balance of sympathy, Wesker also comes up with one of the most honest admissions I've heard on the British stage in a long time: the acknowledgement by Jenny's father that there is a tactile pleasure in the bathing, handling and kissing of children that stops short of sexual abuse. The speech is delivered by Jeremy Child with fervent candour. It also underlines Wesker's key point: that proven child abuse is wicked, but if we deny the joy of sensual physical contact between parent and child we are destroying family life.
Even if the play is not perfect - the family friend unable to repress his own memories of the Nazi death camps smacks too much of an antithetical device - it is brave, honest and urgent. It is also well directed by Andy Hay, neatly designed by Tom Piper, and strongly acted by all concerned, including Nicola Barber as the accusatory Jenny and Rosemary McHale as her defiant mother. In the end, the play is a vehement assertion of the validity of the nuclear family and of the pleasurable intimacy of the parent-child relationship. It is, I suspect, the promotion of such unfashionable ideas that makes Wesker the British theatre's congenital outsider.
• Denial is at Bristol Old Vic (0117-987 7877) till June 10.
