11 and 12 is a minutely controlled offering from a theatre-maker who tends now to be caricatured as a modern Prospero – an exiled magician, rapt in studies that, if not exactly secret, are recondite. 

The reverence with which Peter Brook is regarded can seem suffocating, and no one is more aware of this than Brook himself, whose intellectual steeliness is matched by a disdain for those who label him a guru.

The inspiration for 11 and 12 is a novel by Malian author Amadou Hampaté Bâ, adapted here by Marie-Hélène Estienne. It shows how a tiny incident can have big repercussions, and allows reflections on large issues of faith, truth, social divisions and tolerance.

In a community in French-occupied Mali, apparently in the Thirties, the leader of a Muslim religious group turns up late one day for worship. In order to spare his blushes, a prayer that is normally recited 11 times is recited one time more. This leads to a theological dispute that, as it develops, comprehends a clutch of personal, tribal and colonial maladies — showing above all how religion is manipulated to turn different groups against each other. 

This is promisingly rich terrain. Brook has long been an explorer of theatre’s processes, and has argued that their perfect achievement is characterised by density, in which messages crowd together and overlap. 11 and 12 doesn’t have that density. The storytelling is didactic, po-faced and slow. The performances are committed, yet not engaging. The highlight, in fact, is Toshi Tsuchitori’s music, articulated with great subtlety. 

The experience reminded me — albeit at a lower tempo — of seeing dervishes in action: the wisdom and spiritual seriousness feel remote, and what remains is a methodical asceticism that creates some arresting images but opens no doors.  
Jerusalem, until 24 April. Information: 0844 579 1940. 11 and 12, until 27 February. Information: 0845 120 7550.