Instead of treating John Osborne's Look Back in Anger as a period-piece set in aspic, Alexander Gilmour has given the play an exciting, new dynamic and made a remarkable directorial debut.

By casting the black actor Jimmy Akingbola as Jimmy Porter, Osborne's splenetic, working-class rebel without a cause, Gilmour strikes no predictable blows for politically correct casting. Instead he changes and intensifies the class-related, social and sexual tensions. Porter rains down endless, imaginative abuse upon his ironically servile middleclass girlfriend, Alison. She suffers his contempt and cruelty in a stoic silence, locked in a sado-masochistic affair.

Here, though, Akingbola's Jamaican Jimmy incarnates a nightmare of racist, class-obsessed Britain in the 1950s when black immigrant males were reckoned the quintessence of seductive, sexual potency for errant white girls. In this reconstituted Look Back in Anger a sheltered, unsophisticated girl from a white, middle-class family is seduced not just by a working-class man, but by a black immigrant. From this perspective the character of Alison acquires fresh pathos and is played with riveting poignancy by Laura Dos Santos as a dejected, pregnant victim of a lover she desires but whose cruelty she cannot bear.

The pacific flat-mate, Simon Harrison's Cliff, offers an ordinary kindness she finds dull in comparison. An impressive Akingbola, though small of stature duly looms large, aggressive and passionate as he launches Osborne's eloquent, repetitive fusillades of abuse against an exhausted, elderly England set in its ways and a girlfriend captured from a class he effects to despise. His unsentimental performance reveals the essential Porter as a self-pitying, sentimental exploiter of vulnerable women who are charmed by his vitality.

Gilmour's clever production conveys a vivid sense of life in a cramped, rented attic in 1950s London. The only sounds of Sunday life are church bells and Jimmy's trumpet. I am not, though, dissuaded from my conviction that Look Back in Anger's fame owes everything to the force of its language. It describes a misbegotten love affair, interrupted when Sally Leonard in terrific, sexy form as Alison's actress friend, comes to visit and stays to fall for Jimmy. It is tempered by a superbly wistful Gary Raymond as Alison's military father. In the end it falls serious victim to the repetitive strain of Porter's inconsequential, scatter-gun rage.

Until 26 July (020 7287 2875).