Twenty years ago to the month, in the year of Australia's bicentenary, Timberlake Wertenbaker's Our Country's Good premiered at the Royal Court Theatre.

This harrowing depiction of life in the penal colony of Botany Bay (based on Thomas Keneally's novel The Playmaker) attracted huge acclaim, not least perhaps because of its focus on the country's first drama production, a convict version of George Farquhar's The Recruiting Officer.

Since we critics must necessarily celebrate "the transforming power of drama itself" — to quote the Guardian's Michael Billington in his original review — its laudatory reception was perhaps not surprising.

Watching the well-staged revival at the Watermill Theatre this week, however, I found a play with faults only too apparent. The main one derives from the very fact of its being what one might daringly call a 'play for luvvies'. Conceived in collaboration between Ms Wertenbaker, director Max Stafford-Clark and the ten members of the original cast, the piece superimposes the professional preoccupations of its performers on the characters they portray — or, rather, on these characters as they play their various parts in The Recruiting Officer.

Thus, for instance, we find the well-drilled convict wordsmith Wisehammer (Simon Thorp) complaining that the doubling up of roles in the Farquhar will "confuse the audience". To this the mild-mannered producer, Second Lieutenant Ralph Clark, replies that an attentive audience will follow quite easily — and that "people who can't pay attention should not go to the theatre".

At this, the Watermill audience — recognising ourselves among the attentive elite — will feel a warm glow of satisfaction. For we, too, are being presented with a doubling up in all parts save that of Ralph Clark (the excellent Orlando Wells), director Alex Clifton having followed Max Stafford-Clark's lead over who plays what. All very flattering to be sure, but unlikely to assist in our suspension of disbelief.

That said, this production provides an engrossing encounter with life as it was led by men and women forced to leave Britain "for our country's good" and those — some bad, some good but all well-intentioned — sent to guard over them. The floggings and hangings, the hunger and filth, the drunkenness and degrading sex are bound to dismay and shock. Always, however, we look with the far-sighted Governor (Simon Thorp, again) for an answer to the question: "How do we know what humanity lies under the rags and filth?"

The play ends as The Recruiting Officer begins, with Australia's first actors advancing upwards into a blaze of light to the triumphant accompaniment of Beethoven's Fifth Symphony. This is music, arguably, whose power to "chasten and subdue" considerably exceeds anything ever offered in this respect across the footlights.

Our Country's Good is at the Watermill Theatre, Bagnor, near Newbury, until October 25. Box office: telephone 01635 46044 (www.watermill.org.uk).