After all, ever since Maggie Smith played Muriel Spark's dangerous heroine in the film, Miss Brodie has threatened to coarsen into a purely camp turn.
But Patricia Hodge, who now takes brilliant possession of the role in Alan Strachan's revival of the Jay Presson Allen adaptation, lets you see that it's actually a strange form of emotional repression, of a libido gone haywire, that has turned this war-bereaved Thirties spinster into a woman who lives through her elite cadre of disciples, to whom she offers apparent freedom from bourgeois stuffiness but whose destinies she is out to control.
Every nuance of the comedy is there in Miss Hodge's performance, particularly in the marvellous encounters with Edith Macarthur's disapproving headmistress. 'Chrysanthemums - such serviceable flowers,' Hodge declares, glancing at her boss's vase and inflecting the line with such serene disdain you expect the blooms to curl up and die on the spot.
She maintains the balance between what is magnificent in Miss Brodie with superb aplomb, but also gives out early hints of what is incipiently tragic about this 'born fascist'.
If the actress's fragile, bone china beauty serves to make her thoroughly convincing as a sort of teacher who would stir the hormones of pre-pubescent girls, it also brings out the paradoxically ascetic side of Miss Brodie's sensuality. When she slaps her former lover, the art teacher (David Yelland), you can really feel in the unsettling release of tension that this has been their first physical contact for three years. And in her misguided confidence that she's got all her acolytes taped, Hodge lets you see a woman who is as much a danger to herself as to them.
The 'creme de la creme' are a bit low- cholesterol in this production, though Jackie Morrison gives a splendidly judged portrayal of the clever pupil who, recruited to be Miss Brodie's spy, eventually becomes her betrayer. The Presson Allen adaptation, with its clunky flashback structure of the traitor-turned-nun being interviewed about her life years later by an American journalist, has none of the feline deftness of the novel's contrasting flash- forward technique. With sets constantly sliding on and off, the show feels both choppy and lumbering and the final stage picture with Miss Brodie, the nun and her younger self all picked out by spotlight can't be accused of over-subtlety in reminding you of their life-altering inter-relation. The production is worth seeing, though, for Hodge, who unites the audience in a communal schoolgirl crush.
'The Prime of Miss Jean Brodie', Strand Theatre, London WC2 (071-379 5062)