Cymbeline, Swan Theatre, Stratford-upon-Avon

Given that Cymbeline is such a mishmash - decadent Romans wagering on a lady's honour, sturdy Romans invading Britain, magic potions, stolen babies, a flying visit from Jupiter - one might hope a director would at least impose some visual coherence. Yet, in Dominique Cooke's version, the design, by Rae Smith, piles artifice upon confusion. While the fashionable Romans, in white suits and sunglasses, seem to have stepped out of La Dolce Vita, the Ancient Britons have clearly visited last year's Aztec exhibition - and been deeply impressed. King Cymbeline and his queen wear feather cloaks, and their courtiers have plumage sprouting from their trousers. When Daniel Evans's Posthumus fiercely denounces the other sex, his intensity is compromised by his flower-topped and feather-bordered lapels.

Meanwhile, Imogen, the king's daughter, strides about in a Greek- goddess gown over her Birkenstocks, while the queen's son, the nefarious Cloten, strives to appear menacing in a diamante shrug. Even Morgan, the robust mountaineer, sports a tattoo of the type made famous by David Beckham. All this fashion distraction fragments and trivialises what is already pretty silly. It would be an exaggeration to say that the good people in this Cymbeline are very, very good, and the bad ones are horrid, but there is a definite imbalance in the strength of the acting by evildoers and victims.

As the wicked queen, Ishia Bennison staggers and swaggers on her high heels, sticking out her hip and hoisting her shoulders up and down like Miss John Wayne. Anton Lesser's Iachimo, the Italian who bets he can seduce Imogen, is so slimy it's hard to believe that she or her husband (Posthumus) would be taken in by him for a minute. With opponents like these, the triumph of the good never seems seriously in doubt. Paul Chahidi, as Cloten, is dependably droll when called upon to play the fool, but his brutishness is that of a villain in Gilbert and Sullivan. When he puts on Postumus's clothing, his disgust is obviously caused not by the garments' meanness but by their injury to his fashion sense. David Horovitch, the king who is not so much evil as misguided, is half good: his voice is very beautiful, but it might be issuing from a wooden doll with a Paul Schofield record inside.

In the second half, though, once the costumes have been drenched in mud and blood, and the good people become more active, the play attains a greater power. Christopher Godwin is a tremendously fit Morgan, and he and his two sons, Daniel Hawksford and Simon Trinder, are charming advertisements for the simple life. Posthumus's anguish and insecurity come more strongly into focus: one can even forgive, in this context, his lack of face and crazed revenge. The star of the evening, however, is Emma Fielding, whose Imogen brilliantly personifies virtue. In masculine disguise she is transformed within as well as without, seeing the world through different eyes. The characterisation loses something from her want of vulnerability, but her gentleness in the final reunion scene achieves a touching sense of wonder.

Praise is also due the property department for a splendid effect whose surprise I do not want to spoil. I'll just say, for now, my hat is off to them.

To 7 November (0870 609 1110)