Theatre review: The Enlightenment House, The Georgian House, Edinburgh ***

Heritage theatre has its limitations as an art form. Yet there is something deeply satisfying about watching a witty evocation of the past in the very place that inspired the story; and this Christmas, the National Trust for Scotland has had the bright '“ even enlightened '“ idea of commissioning award-winning director Ben Harrison to create a 'play in five rooms' for the Georgian House in Charlotte Square.

Designed by Robert Adam and completed in 1820, Charlotte Square is one of the world’s finest architectural expressions of the intellectual and scientific spirit of the Age of Enlightenment; and it’s Adam, played by Mark Kydd, who greets us as we enter the house, describing his passion for the elegant and spacious classical forms of the square he did not live to see built.

Then, with a little slip in time, we find ourselves in the dining room with Adam Smith and David Hume – both of whom were dead long before Charlotte Square was completed. They play games of wit and intellectual inquiry over their venison dinner but are suddenly taken aback to notice a group of interlopers (the audience) watching them – people with strange boyish clothes, gleaming white teeth and no body odour.

And from that moment, the show develops into an increasingly light-hearted and entertaining exchange of incredulities between the characters’ time and ours, as we head into the bedroom to meet the frustrated feminist novelist Susan Ferrier, to the upstairs library for another encounter with Hume and Smith (who listen with amazed admiration to the sound of a female First Minister chairing a rowdy cabinet meeting in Bute House next door), then into the drawing room for a dancing lesson and finally to the gleaming kitchen, where Mrs McCardie the cook reigns supreme.

For all its wit, Harrison’s script is neither very beautiful nor very profound.

Yet David Paul Jones’s music leads us thoughtfully through the rooms to a poignant final moment with the wonderful Nicola Roy as Mrs McCardie; Tom McGovern and Christopher Craig act up a genial storm as Smith and Hume. And in the end, the show comes as a simple but vivid reminder of how many of the basic decencies and equalities we now take for granted are a result of that fierce Enlightenment belief in human reason and progress; and of how much we stand to lose, if we fail to cherish that spirit of inquiry and optimism in our own time. - Joyce McMillan

The Georgian House, Charlotte Square, Edinburgh, until 5 January.