Edinburgh 2013: The Radicalisation of Bradley Manning - Tim Price's play is a sympathetic portrait of the Wiki-leaker

Radicalisation of Bradley Manning (Richard Campbell, National Theatre Wales)

“Wales is a radical country,” declare TV screens in the four corners of an Edinburgh school hall. And “Bradley Manning is Welsh” we are also told - as a definitive full-stop to a litany of descriptions of who and what kind of hero or traitor, dumb kid or torture-victim the Wiki-leaker is.

The rest of Tim Price's play will slickly attempt to show the links between these statements, imagining Manning’s school days in Pembrokeshire. They're intercut with filmic swiftness with later scenes from his life – how the tech nerd joined the army because he couldn’t afford college, and how, amid the strain of being bullied and beaten by other soldiers and witnessing the horrors unfolding in Iraq, he leaked huge tranches of data stolen from the US military.

This National Theatre Wales show, originally staged last year, is obviously a timely addition to the Fringe – Manning will be sentenced this week, facing up to 90 years in prison, with the prosecution calling for 60.

The real-life school setting is neat, and in the – wholly imagined – scenes at a Haverfordwest high, Manning's class learn about Welsh revolutionaries, the Rebecca Riots, the Newport and Merthyr Risings. The subject and definition of martyrdom is explored, and Manning proves himself capable of both barn-storming rhetoric, and of breaking the rules to follow his convictions. It's schematic, but effective, Price convincingly envisioning an education that sowed for the seeds for this 21-year-old's extraordinary action just a few years later.

The show is fast paced, with a strong cast of six constantly dashing around, making economic use of six chairs, a table and a few duvets to create a huge variety of times and locations. They swap roles too - whoever wears the glasses is Manning, creating an every-man conceit; a little jarring at first, but they quickly establish a natural rhythm, and director John E McGrath has a firm hand on this wide-ranging, quick-changing material.

It’s an hugely sympathetic portrait, although Manning is presented as personally troubled as well as radicalised: the bullying, a relationship break-up, a sense of never fitting in, an anxiety about the injustice of the war he is helping wage, and a desire for some kind of personal glory all weigh heavily on a naturally explosive personality. This is a troubled man, and his decision - though brave - is also rash. It sure makes for compelling drama, too.

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