The National's amazing current winning streak continues with Elmina's Kitchen, a bright and blistering blast of a play that lives up to incoming artistic director Nicholas Hytner's stated desire to widen the embrace of the audience and artists that his theatre can attract. (In a recent interview with me, he said: "I don't want to programme for only one section of the greater national public. We have to be completely open, and try to address everyone.)"

Black audiences and more specifically black voices have been largely neglected here until now. Only two American plays by August Wilson - Ma Rainey's Black Bottom and a briefly imported production of Jitney - and only one black and British-written play, Sing Yer Heart Out for the Lads by Roy Williams (briefly seen in the Lyttelton Loft studio season last year), have been produced on the South Bank in the last quarter of a century or so.

But Casualty television star turned playwright Kwame Kwei-Armah's pertinent and provocative play brings us searingly up-to-date with a trip down Hackney's Murder Mile, where a powerful family drama is played out around three generations of men. Deli, who runs the West Indian café of the title, has himself served time in prison for GBH, and in the course of the play his unseen brother dies in crime. Their long-absent father, Clifton, returns from the West Indies, and there's obviously a huge void between him and his surviving son. But the centre of the play is Deli's desire to prevent his own adolescent son from being dragged into a life of yardie crime.

As Kwei-Armah says in a programme interview, "I'm concerned about the rites of passage of black youths. Among a certain section of society, the badge of blackness is earned through the façade of criminality. Somehow being black means you have to be the baddest man on the block, you have to be able to carry your Tech.9."

But if that suggests an earnest and critical subject - and it is, uncompromisingly so - his play delivers it in a beautifully observed, brilliantly distilled play of character and characters, revealed in crackling, colloquial dialogue that is as vivid and invigorating as it is earthy. (There's also a terrific in-joke when one character says to another, "You been watching too much Casualty, mate").

Though Angus Jackson's leisurely production may sometimes lack urgency (and Bunny Christie's design of the café is a little too pristine), it can't suppress the vibrancy of the writing or the performances. There's an electrifying performance from Paterson Joseph as the café owner, and a superb ensemble around him that also includes the wonderful Oscar James as one of the café customers and Shaun Parkes as a local baddie.

- Mark Shenton