Garlanded with theatre awards and generating daily queues for returns during its 2007 Barbican season Simon McBurney’s A Disappearing Number stages a welcome return visit. My second viewing of this metaphysical mystery tour of the world of higher mathematics leaves me a little less dazzled and more critical of McBurney’s extraordinary project but still beguiled. The attractive stratagem lets us see mathematics and the complex pursuit of numbers as mysterious, magic and even life-enhancing, despite premature death’s intrusive presence.

Shuttling between present-day London, India and early 20th-century Cambridge, with video film, Nitin Sawhney’s music and a revolving blackboard to help mark the time-jumbled shifts of scene, McBurney sets two stories about mathematicians in reverberative counterpoint. The interest lies more in the mathematical than the personal.

A Cambridge maths professor, David Annen’s GH Hardy, plays host to an Indian Brahmin clerk, with a genius for numbers. McBurney prudishly ignores the crucial though covert gay element in their relationship. He deals more interestingly with his fictitious, present-day mathematician. Saskia Reeves’s dowdy, fortyish lecturer, Ruth Minnen, is poignantly surprised by love in the shape of the Indian-American financier, Al.

“Mathematicians are only makers of patterns,” Hardy says and we glimpse more than one: Ruth’s lecture introduces us to notions of infinity and numbers going on for ever, of how time is a continuum with no gaps. Dead of an aneurysm at 43, having failed to reach the goal of motherhood, Ruth leaves Al a message, envisaging how one day her ashes will be fused with his, true lovers linked in time, through time to infinity. It is, I deduce, a brilliant mathematical deduction.

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