Boris Johnson may be thrilled and the Queen impressed by the progress made on the Olympic badlands in East London, but their pleasure is emphatically not shared by the fictional Romanies in Natasha Langridge’s lively if sentimental new play. For Anna Carteret’s wonderfully doughty old granny and her relatives it means losing their long-time home to the bulldozers, and all for a posh pool and “17 days of synchronised swimming”. Once again it looks as though they’ll have to choose one of two horrors: endless travelling punctuated by racist attacks, or a sedentary life in a drear flat on a hostile council estate.

But all this gives Langridge’s play its context, not its centre. That belongs to an ethnic variation on the Romeo and Juliet story. Alex Waldmann’s Joe is a “gorger”, or non-Gypsy, who comes to the wire separating the Romany encampment from Cockney civilisation to court Jade Williams’s Pearl, who is unofficially betrothed to one of her tribe’s most eligible hunks. She falls for Joe, escapes with him, tells fortunes at rock concerts and, in the evening’s oddest sequence, draws a knife on him in a violent quarrel. Couldn’t Langridge have found a more plausible way of dramatising the clash of cultures than have her bump off a bunny with a stone and disgust a boy who only wanted to buy a sandwich by skinning, eviscerating and trying to roast it?

But then there’s much about their relationship, up to a barely motivated reconciliation, that isn’t quite credible. Only in self-consciously “literary” plays do East London boys say things such as: “No light anywhere but in her brightness life like I never seen.” There were several moments when I thought Langridge trusted her vocabulary too much, her fine young actors too little. Yet there were other times when her language took off: a description of the horse-dealing at Appleby Fair observed with envy and a captivating excitement by Joe, another when the same boy relives a bare-knuckle boxing bout with a Romany rival.

And by the end Langridge has communicated her fascination with a tiny, embattled world whose people feel they are hated “for being free”. That’s her play’s weakness, because it brings with it a certain cultural obsequiousness. It’s also its strength.

Box office: 020-7478 0100, to Nov 21

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