Comedian, Observer commentator and experimental-music fan Stewart Lee has a great line about the branch of Nando's that displaced his favourite jazz club: "They ought to introduce a new menu which, through improvisation and chance procedure, redefines the parameters of what chicken could be."

His current project uses improvisation and chance procedure to redefine what a standup gig might become. In truth, it's not a standup show at all, given that Lee is seated and reading from a script – not his own, but John Cage's anthology of short stories, epigrams and mini-essays which the composer recorded in 1959 while his regular collaborator, David Tudor, performed improvised music in another room.

The minute-long readings, shuffled and read out in random order, produce an effect similar to riffling through the card index system of Cage's subconscious. Recurrent themes that emerged from this performance included musings on eastern poetry, Cage's scientific interest in mushrooms and recollections of Schoenberg's composition classes at UCLA, including a great piece of advice conveyed to a struggling young pianist that the key to playing a Beethoven sonata without mistakes is to avoid making any.

With the 60-second duration of each reading dictated by a stopwatch, Lee's delivery ranged from Pinteresque ponderousness to racing-commentator gabble; while the experienced Cage authorities and improvisers Tania Chen and Steve Beresford provided an entirely unrelated accompaniment using a prepared piano, a pair of Stylophones and bright, plastic laptops designed to teach children to spell. Some of Beresford's more alarming interjections might have been taken for signals to evacuate the building; as for the likelihood of jazz chicken appearing at Nando's, John Cage was once spotted in the Huddersfield branch of Pizza Hut, so stranger things have occurred.

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