THEATRE Light Shining in Buckinghamshire Royal National Theatre Mobile Production seen on tour at St Martin's Church, Brighton

The temptation to look for reflections of the present in the past is always strong, and you can find such reflections in any period if you look hard enough. The historian Barbara Tuchman, in her book A Distant Mirror, saw the 20th century reflected best by the wars, plagues and schisms of the 14th. Watching Caryl Churchill's remarkable 1976 play Light Shining in Buckinghamshire, which revolves around the millenarian hopes and anxieties of the Diggers, Ranters and Levellers of the English Civil War, it's impossible not to hear pre-echoes of our own times, at the end of the millennium. It's impossible, too, not to see some contemporary applications in Churchill's picture of the agonies of a dispossessed, politically excluded class.

The echoes are amplified in Mark Wing-Davey's new touring production for the National Theatre by the self-conscious anachronism of Madeline Herbert's design. The cast are sometimes clothed in recognisably 17th- century garb, sometimes in timeless rags, sometimes in defiantly modern modes (at one point, the Ranting preacher Cobbe delivers a sermon in what looks to be a see-through PVC frock). The props have apparently been welded together from old bedsteads and mattress springs, lending an air of post- industrial decay. Meanwhile, a programme note by the environmental activist George Monbiot points out the influence of the Diggers on modern radical groups such as The Land Is Ours, who occupied the Guinness brewery site in Wandsworth earlier this year.

Some of the historical parallels are almost too close for comfort. One scene towards the end of the play has a Parliamentary commander arriving to take over an estate, declaring to the vicar that he is no old-fashioned squire, while making it reassuringly clear that the only changes he intends to make to the way things are run are ones of tone, not policy. Hard to believe that this was written nearly two decades before Tony Blair took over the Labour Party.

The great strength of Churchill's play, though, is that it manages to urge the connections between then and now without losing sight of the essential strangeness of the past. Throughout the play's fragmented structure, in which actors chop and change from character to character in a series of mostly short scenes, Churchill retains an almost documentary faithfulness to the visionary language and imagery of the times. Some of the most absorbing scenes, however, are virtually transcripts of real events - such as the Putney debates of 1647, in which common soldiers argued for a radical programme of democratic reform in opposition to Oliver Cromwell.

Wing-Davey's six-strong cast are mostly good, apart from some erratic regional accents, and Tim Welton and Patrick Brennan are outstanding - though their very similar physiques make it hard to tell them apart in some scenes. That mightn't matter in a more forgiving venue but, aside from being theologically inappropriate (far too many graven images), St Martin's Church in Brighton offered terrible sightlines and a lousy acoustic. If you can see it elsewhere, though, you probably should.

RNT Cottesloe 9-11, 20-23 Jan and in rep from 17 Feb to 5 March (booking: 0171-928 2252) and touring to 22 March

Robert Hanks