As the Olympics come to London, Mayor Boris Johnson finds himself on the global stage.
Actor Benedict Cumberbatch on depicting Alan Turing in The Imitation Game
Nico Muhly discusses his new song cycle Sentences.
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Mark Ravenhill on scientist Alan Turing
Cycling hero Bradley Wiggins, who MPs have accused of 'crossing an ethical line'.
Mathematician and code-breaker Alan Turing, and his role in the invention of the computer.