Sketching, Wilton's Music Hall, review - less a dynamic babble than a disconsolate babel

It sounds like a marriage made in heaven. Charles Dickens and James Graham – both great chroniclers of the ambitions, hypocrisies, and eccentricities of their respective ages – have been brought together to tell London’s story through irreverent portraits of its high life and low life.

This modern Sketches by Boz reboots the Victorian original to embrace computer hackers, a Syrian asylum seeker, and mock conceptual artists among others. The result is a lively, structurally ambitious work that somehow fails to add up to the sum of its potentially fascinating parts.

Graham – who has repeatedly wowed both theatre and TV audiences with punchy, searingly insightful works including This House and Ink – has decided to work with a team of writers rather than developing this latest endeavour solo. There’s an obvious logic in trying to recreate the whirligig of London life through a multiplicity of authorial voices, yet here the resulting unevenness of tone means that it’s less a dynamic babble than a disconsolate babel.

Like the original the play is divided into distinct chapters for each character, with some direct echoes – The Pawnbroker’s Shop, for instance, becomes Mo’s Second Hand Shop. A cast of five divides up the parts, intercutting episodes from the different storylines. In one – Himansu Hojan’s The Hand of Hozan – a sewer worker turns up with a package for a policewoman who mistakenly thinks it’s a bomb, in another a girl, Katie, has a will-they-or-won’t-they meeting with her ex-boyfriend Tom. Fragments of lives play out briefly before us before being displaced by other lives – we see thieves, stage-door hands, a grieving wife obsessed by a songbird, migrants – a kaleidoscope of human existence against the eternal hum of the city.

When you’re sketching characters this swiftly, you’re walking a thin line between ellipsis and caricature, and one of the problems with the early scenes is that the writing often fails to stay the right side of that line. The lesbian squatters who pretend to be conceptual artists, for instance, make no joke that hasn’t already been heard a million times this side of Shoreditch, while Katie and Tom seem to tread territory familiar from the most threadbare of romcoms.

There are glimmers of gold though, and as the action progresses the storylines become more satisfyingly unexpected. The sewer worker and the policewoman end up on a fascinating quest despite its bathetic ending, while a twist suddenly reveals Graham’s Katie and Tom in an astonishing new light, reminding us of why he’s such an acclaimed writer.

Director Thomas Hescott keeps the pace engagingly fluid, with Daniel Denton’s ingeniously sketched video designs of different London landmarks bringing a stylish immediacy to each scene change. Yet the feeling in the earlier scenes that the characters don’t have enough emotional hinterland to draw the audience in is a question of performance as much as writing. Graham deliberately creates an atmosphere of improvisation at the play’s start, but this needs to be balanced by the actors demonstrating real conviction as they inhabit each role. In his drive to maintain momentum, Hescott has sacrificed crucial depth.

There are two overarching themes holding all the different storylines together – one being a forthcoming mayoral election, and the other a plot by a man called Peter Piper to "steal the internet". As the storylines first run parallel to each other and then intertwine it should create a satisfying pattern – as it is, it mainly leaves the audience member with a sense of how many holes there are. Those glimmers of gold are a reminder of what a sadly missed opportunity this is – not so much a Short Cuts for 21st-century London as a series of ragged off-cuts. It would be fascinating to see Graham update another Dickens – his take on the civil justice system in Bleak House springs to mind, or the local-government satirising Little Dorrit – but this Sketching sadly can be described as little more than, well, sketchy.

• Sketching at Wilton's Music Hall until 27 October
• Read more theatre reviews at theartsdesk

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