A Dream Play, Cottesloe, NT, London

It's a moot point whether Katie Mitchell ought to be had up for false advertising. According to the posters and the cover of the programme, what is on offer at the Cottesloe is " A Dream Play by August Strindberg in a new version by Caryl Churchill, with additional material by Katie Mitchell and the Company". But it is some minutes before anything recognisable as Strindberg turns up; and then it is given such a different context that it feels like something entirely new.

It's a moot point whether Katie Mitchell ought to be had up for false advertising. According to the posters and the cover of the programme, what is on offer at the Cottesloe is " A Dream Play by August Strindberg in a new version by Caryl Churchill, with additional material by Katie Mitchell and the Company". But it is some minutes before anything recognisable as Strindberg turns up; and then it is given such a different context that it feels like something entirely new.

Strindberg's original is a compelling and attractive work, but also baffling and, as far as staging it goes, intractable. In it, the author tried "to imitate the inconsequent yet transparently logical shape of a dream". Time speeds up and slows down, scenes dissolve abruptly into one another, events occur with no regard to cause and effect, images and patterns are repeated and reconfigured. People marry within seconds of meeting, die and wake up again; names and identities shift and blur, so that strangers are suddenly recognised as intimates, one individual is somehow several different people. Any performance places tremendous strains on the audience's attention. My own feeling is that it is best appreciated on the page, and stagings should be treated as sources of images to flesh out the text.

In his introduction, Strindberg spoke of the ruling consciousness of the dreamer. Mitchell echoes this in a programme note, then goes on: "So we had to pick a dreamer from the characters in the play." This is a non sequitur (one not reflected in Churchill's published text) - the dreamer might easily be the author or the spectator. By taking this tack, Mitchell has transformed the play. What we now have is a dream about the life of Alfred Green, a middle-aged banker in England in the 1950s, whose mother died when he was a child, and who has been twice divorced.

Rather than helping the audience to follow the action, these specifics bring Strindberg down to earth. In the original, a central character is a woman called Agnes, who is also, some of the time at least, a daughter of the gods, descended to observe humanity's misery. Here, Agnes is Alfred's secretary, whom he imagines as an angel, perhaps his saviour. The effect is banal: banker in love with secretary? We're in Reggie Perrin territory. Above all, it is no longer a play that takes the form of a dream, but a play about the mechanics of dreaming.

If this isn't Strindberg, does it work on its own terms? Hard to judge. The staging has moments of magic, images that are genuinely and inexplicably haunting (such as when Alfred lies down in his coffin and the assembled mourners tuck him in). But at times the apparatus offers a very hackneyed notion of dreaming - oops, I'm in public in my underwear! Oh no - now I have to sing to an audience. Technically, it is wonderful - the steady drone behind Christopher Shutt's sound design, Chris Davey's subfusc lighting, Vicki Mortimer's walls that menace and recede. But the feelings it evokes are marooned: a dream is insubstantial; but this is insubstantial in the wrong ways.

Booking to April (020-7452 3000)