Jeremy Charles is an unusual candidate to be Mayor of London. He’s a television presenter who’s just hit the headlines for cuffing a black youth who came at him with a knife. He’s not affiliated to any major political party. And, oh, he’s black himself. With 40 per cent of Londoners coming from an ethnic minority group, could Jeremy be the man to topple Boris in 2012?

One of the big flaws in Kwame Kwei-Armah’s latest play — the second in Not Black and White, the Tricycle’s triptych of dramas about the black British experience this decade — is that you never really buy the idea that Jeremy is the man for the job. Kobna Holdbrook-Smith makes him an engaging character: an articulate, ambitious man impatient with the ghetto mentality of those he’s left behind. But mayor? Come on. Boris does his buffoon thing, but he’s also a scholar, an orator. Ken? One of the all-time great operators. (There he is on the back of the programme, loading his plate at a local tandoori restaurant.) Yet Jeremy is just a pleasant frontman for the black pressure group running his campaign. He’s not special enough for us to buy into the premise for the whole drama.

It’s a play of ideas that needs another draft to make its characters a bit less Legoland. But although it lacks the spark of Kwei-Armah’s earlier work, this remains a superior misfire bolstered by plenty of wit and intelligence.

The dialogue with the political masterminds (Karl Collins, Jaye Griffiths and Abhin Galeya) would look 2-D next to The Thick of It but carries intriguing ideas about how Jeremy should present himself. He doesn’t do “the black thing”, he says. But can he really avoid addressing his own ethnicity?

At its best Seize the Day explores notions of blackness both within and without the black community. Jeremy becomes a mentor to Aml Ameen’s Lavelle, the teen he cuffed. Lavelle’s mum calls him a “race traitor”. Can you change anything without becoming an insider? Can you change anything once you are an insider?

The playwright’s own, spare, well played production holds the attention throughout, but his perspicacity is spread too thin. It’s not quite a gripping political drama, not quite a convincing marital drama — Jeremy has a sullen white wife and a supportive black mistress, neither of whom get much stage time — and not quite a persuasive story about a man finding himself by persevering with a brilliant but difficult teen. It’s the last of these, you suspect, that ended up engaging Kwei-Armah most, which may be why Jeremy’s chances of ousting Boris look dodgy.

Box office: 020-7328 1000. Until Dec 17.

Seize the Day Tricycle, NW6 H H H I I

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