Theatre Blood Knot Gate Theatre, London

`The production seems anachronistic, though it does teach us something of the profound ways in which apartheid was internalised by its unwilling participants'

When Zak gets home from a long, hot day's work, he likes his supper to be ready and his footbath prepared. Morris, therefore, sets the alarm clock to make sure he isn't napping at the crucial moment, then re-sets it so they'll know what time to eat supper, what time to choose a reading from the Bible, then go to bed. But tonight Zak is troubled by a memory of a man called Minnie. Before Morris came back, Minnie used to come by Zak's corrugated-iron township shack almost every night, bringing with him liquor, music and women. However much Morris tries to distract Zak from this memory, with dreams of the farm they are going to buy when their savings tin is full enough, Zak's mind returns to one thing only. "I want woman!" he roars.

Fugard expertly manipulates the power-shifts between the brothers, which allows Wilbert Johnson (as Zak) and Chris Lailey to shine in the roles. Zak plays the "man about the house", but when his brother forbids him to have contact with women, instead suggesting a safe, sanitised correspondence with a pen pal in a distant town, Zak surprisingly submits. When Zak's chosen pen pal sends a photo revealing that she is white, Zak finds the situation thigh-slappingly hilarious. Only Morris understands the grim implications. It's illegal for Zak even to correspond with a white woman.

It seems strange to be watching Athol Fugard's 1961 play now, when apartheid has been officially over for nearly two years, and when the playwright's most recent response to the changing situation, Valley Song, opens at the Royal Court in London shortly. Initially, Blood Knot seems like a gently absurd comedy, and its bitter political twist doesn't inhibit the laughter. The text stipulates that Zak is "a dark-skinned coloured" and Morris is "a light-skinned coloured", though in Jonathan Lloyd's production Morris is white. The naturalism of the piece is loose enough to allow the brothers' situation to be read in a more universal way, and, with this casting, the subtleties of the colour hierarchy under apartheid give way to the broader issue of race.

From here the play departs into dark and savage territory as Zak is forced to understand the truth about his situation. The brothers' memories of their mother diverge significantly; clearly, she is Africa, and though they both loved her, she has favoured them differently. Finally Morris dresses up in the white gentleman's outfit that they have blown all their savings on in a convoluted attempt to cope with the recent arrival of the pen pal. When he is wearing the suit, Morris starts to act like a white man, shouting abuse at his black brother, raining humiliations and even blows on his head.

Through this bizarre and disturbing role-play, Zak gets to learn the full ignominy of his situation, which Wilbert Johnson portrays with a terrible passion and sensitivity. Theatrically it is pure old-fashioned protest theatre, which shows how far Fugard's more mellow recent work has come since then. Again, the production seems anachronistic, though it does teach us something of the profound ways in which apartheid was internalised by its unwilling participants. This is the legacy Mandela's South Africa is coming to terms with now, and, as this play proves, theatre is one way of engaging with that process.

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