That period in our history - the real one, not Hare's "pure fiction" - does invite serious artistic treatment. It was a long-drawn-out farce, or tragedy, depending on one's original view of Blair and New Labour, in which the misplaced faith, hope and love of the idealistic Left in this country was systematically betrayed by New Labour - by its greed, corruption, vanity and intellectual vacuity. Naturally enough, the left-liberal establishment feels outraged, bereft and in desperate need of a new narrative, as such people say.

However, Gethsemane is not more than the narrative we already know; it is less. Seeing only a couple of Shakespeare plays would remind you that politics has always been a very nasty business. What is disappointing in Gethsemane is that the fictional characters are very much less theatrical and astonishing than their true-life doppelgangers. In the play, their roles are stereotypical and two dimensional, apart, at times, from the Home Secretary's. Between them, they offer no explanation - moral, psychological or sociological - of why nearly every one behaves as badly as he or she does.

Hare expects us to find explanation and meaning in his use of the idea of Gethsemane. The stereotypical good woman of the play - the disillusioned teacher-cum-saviour of the minister's abandoned daughter - refers twice to a sort of Gethsemane moment as central to why she has given up teaching for busking on the Underground. She describes it as her "moment of doubt". And in a moment of truth, in the staff-room lavatory, she realises she had to stop all the form-filling and target-chasing and give up.

As the minister's daughter points out to her, that is not exactly what happened at Gethsemane. Jesus did not give up; he "went through with it". That's true, but she too has missed the point of the story. What Jesus "went through with" was complete self-sacrifice for others. The good schoolteacher seems hardly likely to do that, or to be required to; indeed she has already abandoned her pupils. And the steely Home Secretary, who also has a long night of doubt, was wondering only how to survive politically - whether to dump her embarrassing husband or to be loyal to him despite the Prime Minister's threats and so risk her career. All this seems to have very little to do with sacrificing oneself entirely for the good of others - even though trying to do good for others is a claim made by almost everyone in the play.