London: Southwark Playhouse, near London Bridge station
Until Saturday 27 November, daily, 9:30pm (10:40pm)

Atrium: a play within a play about a book within a book – and a contemplation of how slippery our grip on truth can be.  When a dying man, Malcolm, relives his life for his biographer, he finds himself wondering how his story will be received.  He worries, he fantasizes, he embellishes his memories… and you’re never sure quite how much he’s making up as he goes along.

I sometimes felt the same about lead actor Marcus Emerton – but that's to his credit, for his performance is far more disciplined than it first appears.  He banters well with the audience, ad-libbing effortless rejoinders for the most unexpected of remarks, and he’s quite unfazed by the sense of shambles he occasionally creates around him.  When he needs to, though, he can flip the mood in an instant; his more sombre monologues carry an authoritative dignity, and at times – recalling his wife’s suicide, for example – I couldn’t bear to watch his face.

But the downbeat moments don’t last long; for the most part, this is a genuinely funny play.  There’s plenty of laugh-aloud intellectual wit, but there’s a wealth of absurd imagery too.  One woman is dressed as a hot dog.  For no very obvious reason, the biographer wears roller skates.  And then there’s Belt Up’s famous audience interactivity, getting us up on our feet for participatory hijinks – usually just for fun, but occasionally delivering a more thoughtful sting.

Give it a while, and you’ll slowly grasp the serious point to this all: when the fictional Malcolm discusses his fictional audience, real-life playwright James Wilkes is talking about us.  In one particularly delicious moment, Wilkes – speaking through Malcolm – describes exactly how he’s planning to mess with our heads later on.  He explains, in some detail, the psychological trap he’s laid; it couldn’t be clearer if it had a neon arrow on top.  But I still fell headlong into it.  He’d predicted my responses so masterfully, even showing the machine behind the curtain didn’t break the spell.

Ultimately though, for all its tricks, Atrium’s mark on me was fleeting.  I enjoyed it a great deal – but I enjoyed it as a puzzle, not as a parable to cherish and savour.  With the greatest of respect to Wilkes, his youth occasionally shows: his script’s core themes are shouting to be heard among a boisterous crowd of ideas, and it’s exciting to think what this work will become once they’re marshalled into proper formation.

There’s no need to wait, though; as it stands, this play’s more than ready to enjoy.  Get down to the atmospheric Southwark Playhouse, and book your place in the Atrium – for the laughs, for the riddles, for the sheer wonder of it all.  And to find out the answer to one of life's great questions... why is she wearing that hot dog?