To celebrate the centenary of his birth next year, Oxford Theatre Guild look at the tragic life of Enigma machine decoder, computing pioneer and eventual social pariah Alan Turing in their dignified production of High Whitemore’s eighties play Breaking the Code.

A sprawling collection of moments from Turing’s childhood through to his death, the play gives a sense that Turing was ahead of his time. In times of reserve, so-called decency and emotional repression, Turing (Joseph Kenneway) is depicted as wearing his heart on his sleeve.

In his professional life, he discusses his suspicion of patriotism at his interview for the Government Code and Cypher School, for his crucial work in the Second World War.

In his private life, he frankly admits his homosexuality to those closest to him at a time when such acts were imprisonable offences.

Aside from the story, what is most striking here is what is omitted. Although there are explanations of aspects of his work, this is by no means a comprehensive account of how Turing helped to win the war. Neither is it a dissection of his inner turmoil.

It’s also not about bygone attitudes to homosexuality or about Turing’s pioneering work in computers. If anything, the play encourages us to go away and read further about his life and times.

It leaves out, or touches lightly on, reconstructions of key events (including some more pivotal ones). We hear just enough to keep us interested.

In a simple staging by the Guild, what really stands out is the acting. Director Kevin Elliott is careful not to make this hagiographic. Kenneway depicts Turing as a socially awkward, but otherwise stunningly assured man.

He gets excellent support, especially from Wayne Brown as Turing’s sometime lover Ron. A little static at the beginning, the actors free up for a second half which does occasionally veer into melodrama. But, for the most part, this is a restrained, sensitive and thought-provoking evening.