Anyone who has enjoyed Shakespeare’s Macbeth over the years may well be surprised, shocked or delighted to learn that there is much more to expend on that particular tragedy. David Greig’s Dunsinane seems to analyse, in this fascinating production by the National Theatre of Scotland and the Royal Shakespeare Company, a basic precept common to occupying forces – namely if it’s there, and threatening – kill it.

The play opens with Scotland in turmoil. Macbeth and spouse are yesterday’s news and an English peacekeeping force is attempting to smooth the way for future political structures – the reference to present day British forces doing the same job today in the Middle East is timely.

But clashes with the native population are inevitable, and the collision between the idealism of the invaders and the fury of the native population, usher in the idealist Siward (Jonny Phillipas in a well-shaped performance as a man who shows himself to be both fragile and commanding).

Greig’s text is amusing and serious by turns. The occupying soldiery are little more than boys, out for a lark and yet unnerved by the realities of death. The sequences where they tell us of their fears and joys and longings to return home are both touching and yet have a strong touch of reality. One officer longs to leave Scotland’s joyless frozen wilderness and return to the warmer climes of Surrey and his wife and family, but we are still in the Dark Ages and who can tell where the next arrow will come from.

Siobhan Redmond gives a beguiling performance as Gruach, the powerful, scheming, charismatic wife of the dead king. And every congratulation to Sandy Grierson’s Malcolm, a painted king who continually vacillates when it comes to decision-making.

Greig’s writing is richly poetic throughout although not without its longeurs and confusions, where you occasionally wonder just what is happening. But his way of evoking horror as well as passion is beautifully done under Roxana Silbert’s sensitive direction, all of it played out against Robert Innes Hopkins funereal set, as dark as the story and perfect under the snow which cloaks everything as Siward finally quits a game he has lost to wander alone in Scotland’s hostile wilderness.

Until Saturday.