Wild (Hampstead Theatre)

So, Wild is Mike Bartlett (Doctor Foster; King Charles III) doing Edward Snowden. A young American named Andrew sits in a Russian hotel room; he's spilled the secrets of how his government spies on its citizens. He's visited by a representative of a WikiLeaks-style organisation, supposedly there to help. Andrew has, after all, just detonated his own life as well as Western civilisation.

This woman is weirdly chummy yet sarcastic about the present threat to his life, to national security, and to telling the truth about who, exactly, she is. There's Pinter-menace in Caoilfhionn Dunne's exceptionally good performance – and it seems her organisation have their own desire to control Andrew (Jack Farthing).

Still, they talk, and toss about the 'big ideas' you'd expect in a Snowden play: America as a nation founded on freedom that's now "lost its USP"; how groups like WikiLeaks end up as power-addled as those they're trying to expose; how we've all sold our data and privacy. Even the other side of the coin – that governments might genuinely need surveillance to keep us safe – later gets an airing.

You watch, and you think it's all well done – funny interactions, smart dialogue. But aren't some of these arguments a little pat?

But things are not what they seem in James Macdonald's superbly controlled production. The play is less about staging big headline 'themes' that emerge from the Snowden leaks, and more about the individual. Or about using an individual to illuminate some of those themes.

A man arrives, with a similarly coldly amused nonchalance (John MacKay, also terrific), and contradicts what the woman has said. Who is telling the truth? Rattled, now, the assault on Andrew's sense of veracity, and accompanying moral certainty, begins to shift. To tilt.

Andrew experiences (or is thrust into) an identity crisis: who are you when your entire life changes? Who are you when stripped of those you love, alone on the other side of the world? Who do you become when you can't tell what's true anymore? And, by extension, what is our society when we don't know the truth of how it's run and who really runs it?

This honing in on an individual personality is smart. Because the issue of identity is also at the heart of our relationship with global technology. As Wild suggests, we carefully construct our identity – only to give it away online to everyone, for free.

Identity thus becomes a frail thing. Easily created, easily erased, easily faked. But it's not just digital footprint: flesh and blood are eventually shown here to be as malleable as an online profile. And if a person sitting right in front of you can keep hidden who they are, what hope do we have for transparency in our political structures? How can we ever really know what's going on, no matter how many whistles are blown?

This sound like a mad leap – an individual body; a political system – but Bartlett's clever play prods you to forge connections, to go from the micro to the macro.

And theatre is the perfect medium for this. Go on, add one more layer. Because we already know we're watching someone pretending to be real. We know it's only ever going to be fake blood. The slipperiness of what Bartlett's depicting is superbly served by being presented on stage, where phones don't really ring out and walls could be knocked over any time.

But we're not done yet: the final scenes feature a stunning coup de theatre. To say more is to spoil – for the play plays with you, slings you around. It asks you to further question what's gone before, who is who, what's right and wrong, or even just up and down.

Form follows content, and designer Miriam Buether deserves a medal. Wild becomes a wild ride indeed: one that will leave you utterly gripped, at the edge of your seat… and one that will, I hope, allow the reader forgive such clichéd turns of phrase. They're also not quite what they seem.

Wild runs at the Hampstead Theatre until 16 July.