Theatre: Strictly classroom

David Benedict applauds the latest adaptation of `The Prime of Miss Jean Brodie', but sees a production living in the shadow of its free- spirited protagonist

"GIVE ME a girl at an impressionable age, and she's mine for life." As views of the education process go, it's pretty selfish. But then not every teacher is Jean Brodie, and you only have to watch one of the St Trinian's films to know that there is more to girls' schools than Enid Blyton.

The National Theatre had done its bit for the genre, staging Sarah Daniels' Neaptide, Lillian Hellman's The Children's Hour and now turning its attention to The Prime of Miss Jean Brodie.

Jay Presson Allen turned her own doggedly faithful stage adaptation into a film but neither version could hold a candle to Muriel Spark's matchlessly spry novel about a dangerously influential teacher in the Edinburgh of the Thirties who manipulates her girls for her own needs. The play has, nonetheless, done decent service - revived in the West End just four years ago - but for Phyllida Lloyd's extraordinary new production, Allen has substantially revised it. The results of their collaboration are truly remarkable.

The prosaic framing device of a reporter inviting Sister Helena to talk about her schooldays has been scrapped. Better still, Allen and Lloyd have re-thought everything, cutting over-explanatory dialogue and entire scenes. Lloyd has also done away with naturalism. She and the Huntley Muir design team adopt bold colours and visual metaphors. Vast wall frames of school climbing bars double as the grille through which Sister Helena (former Brodie schoolgirl Sandy) speaks, vividly conjuring the cloistered atmosphere of school and nunnery. She also pulls off a master stroke by using children to create all the choral and string music which suffuses the production.

But, and it is a big but, it is not just the schoolgirls who are in thrall to their leader: the production itself is, too. From the second Fiona Shaw swaggers on, hand on hip, it is clear she is taking the high- spirited route.

Teddy (the excellent Nicholas Le Prevost), the art master who loves her, describes her as "the only sex-bestirred object in this stony pile", and he is right. This Miss Brodie toys with everyone and trumpets her delusions from the rooftops. As a comic turn it is ludicrously enjoyable, but it is impossible to believe that this free-spirited woman has been teaching at such a traditional school for more than five minutes. For all her talk, we need to see her deeply conservative streak, or else her Fascism makes no sense.

Shaw's boisterousness infects nearly all the performances, and not all the relationships ring true because of the high mannerism. The scenes between the girls are often very funny, but sometimes you feel as if you are watching out- takes from Daisy Pulls It Off. In the midst of all this, Susannah Wise is very impressive as Miss Brodie's brooding, duplicitous confidante Sandy. Her increasing disenchantment and maturity give the proceedings some much needed weight.

As Oscar Wilde wrote, "each man kills the thing he loves... the coward does it with a kiss". This is precisely what Lloyd has the tearful, torn Sandy/ Sister Helena do at the moment of her betrayal, an action thrillingly prefigured in the opening tableau where the nuns seated all along a table are suddenly transformed into the Brodie girls, and then in a flash into the figures of The Last Supper.

Moments like these cast a tremendous spell. A shame that, in this of all plays, the truth is so compromised by the wilfulness of the central performance.

`The Prime of Miss Jean Brodie', at the Royal National Theatre, Lyttleton, South Bank, London SE1. Box office 0171-452 3000