THEATRE / Lashings of lingo: Paul Taylor reviews Prunella Scales in Alan Franks' black comedy The Mother Tongue at Greenwich Theatre, London

'MMM,' says Dorothy, the frightfully well-bred, old-colonial type contentedly to her daughter and grandson who are assembled round the table, 'tea, proper scones, and sex.' What's in the offing here - an incestuous orgy over the doilies, crumbs getting absolutely everywhere? Not exactly; it turns out that 'sex', in Dorothy's lingo, is just an abbreviation for second helpings: 'That one goes all the way back to St Hilly's' Her conversation is interspersed with the odd Spanish phrase, too, since she's spent 35 years on a posting in Argentina, but it's Brazil, Angela, where a lot of the odd vocab seems to hail from.

Dorothy is the sort of woman who compulsively translates family and friends into a proprietary mythology of upper-class nursery characters. Her talk is peppered with references to such figures as Zigger, Boffo, Moisture, and the Squirrels, and an air of the boarding schoolgirl joke hangs over much of her phraseology: 'Well, chacun a son modus vivendi, I suppose', she says of the daughter's decision to become a working mother again. A quarter of an hour of this jaunty verbal tyranny and you'd want to get her in a dentist's chair and block her mouth with reinforced concrete.

As its title implies, Alan Franks' black comedy, The Mother Tongue, is about oedipal conflicts waged as a clash of languages, but it handles this theme with wearisome predictability. Her Kensington flat having accidentally burnt down, Dorothy (played by Prunella Scales in indomitable regal mode, though with less than majestic grip on some of the lines) billets herself on her daughter, Harriet (a wonderfully believable Gwen Taylor), whose South London home and media-marriage are both in some disrepair. 'This house is well dysfunctional,' remarks Jeremy, her consciously downmarket, comprehensive school-educated son (attractively portrayed by Jamie Glover) and he's not just referring to the faulty cistern. Equipped with the sort of improbable eloquence granted to characters in bad plays, this youth acts as cheery resident-interpreter, decoding for his grandmother the psycho-babble spouted by the members of his mother's crudely caricatured Women's Support Group. The phrase 'it's your choice', he explains, is 'stripped pine jargon for 'tough titty' '.

You know, watching Richard Cottrell's game production, that it's only a matter of time before Dorothy starts rumly appropriating the expressions of the soul-sisterhood ('justified anger' etc) to win points in arguments, and that she will end up accusing her daughter of sounding just like her mother. You also brace yourself for the big guts-out-on-the-table that is clearly brewing for Act Two. Franks wants us to feel ambivalently about the daughter's eventual violent outburst against Dorothy's intrusiveness and protective myth-making; but he engineers this in a mechanical manner, inserting just before it a scene where, while the others are out, the old woman discovers that her flat was uninsured (the details of her lack of cover sounding terribly contrived) and that she has therefore lost everything.

So when the showdown takes place (in best stagey manner, before as large an onstage audience as possible) and Harriet gives the family skeletons (parents' sado-masochistic sex-games; the fact that Dorothy is barred from her other daughter's house) a surprise airing, we know (even if she doesn't) that it's a poor homeless sexagenarian that's being reduced to a heap on the floor. And does this lady of the old school rise and rally with a dignified stoicism and a drily witty defence of her own privacy that leaves you feeling that there might, after all, be something to be said for the cramping standards she's lived by? You betcha. 'Detach with love' is a bit of the feminist-speak on parade here. From this over-written, cliched, badly structured drama, you detach with relief.

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(Photograph omitted)