Les Blancs had a troubled birth. In 1965 several unfinished drafts of the play were entrusted by its dying author, Lorraine Hansberry, to her ex-husband, Robert Nemiroff, who mounted a debut production in New York in 1970. Nemiroff has created a fresh version with the help of a ‘dramaturg’ (or ‘colleague’, in English) named Drew Lichtenberg who believes not only that this ramshackle script is a masterpiece but also that Hansberry belongs in the first rank of dramatists alongside Ibsen, Sophocles and Aeschylus. This does not bode well. But the result is surprisingly good. Or good-ish.

The setting is a nameless African colony populated by do-gooding Europeans, angry freedom fighters and a thuggish soldiery overseen by a British army major who happens to be a psychopathic racist. The atmosphere of the tropics is conjured brilliantly and Soutra Gilmour’s lavish designs are a true feast for the eye. There’s music, too, from white-gowned matriarchs who warble native choruses and pluck away at crude, hand-made instruments. Stock-still peasants watch the action with pots on their heads. Just occasionally I felt I was watching an arts-and-crafts display at the Commonwealth Institute but the show earns good marks for making the Olivier’s space work well.

The play sets out to demonstrate that Africa’s greatest natural asset is self-delusion. Westerners arrive there in search of self-fulfilment and dress it up as altruism. We meet a photojournalist, Morris, who wants to capture quaint images of docile savagery and who invites an African intellectual, Tshembe, for a chinwag over some whisky. Tshembe coolly points out that three centuries of exploitation can’t be eliminated in a cloud of liquor fumes. This is powerfully done. But there are distortions too. The scene where the mad major (Clive Francis) executes an African servant while the Europeans look on inertly seems improbable and highly manipulative. (But liberals who enjoy scratching their guilt will wish there were more such opportunities for self-flagellation.)

This interesting, gruelling and occasionally silly play stands very little chance of becoming a classic. Hansberry, like Bernard Shaw, is too eloquent for her own good. She likes her characters to state their opinions rather than to suffer and learn from their consequences. And there are too many false predictions. Tshembe has a forlorn dream that one day he may settle down in Europe with his red-haired wife and mixed-race child. Yet this is precisely the life being enjoyed now by millions of Africans. His fellow nationalist, Ngago, argues that Africa used to be a haven of peace and good governance until the pesky Europeans barged in and ruined it all. He also believes that Africa without the whites will return to its natural state of happiness and freedom. Something went wrong there.

The oddly named Cyprus Avenue is a violent farce starring Stephen Rea. At first I thought I’d stumbled into a biographical drama about Gordon Brown because Rea bears an uncanny resemblance to the ex-prime minister. He has the same air of hurt melancholy, the puffy, doleful face, the fine luxuriance of wavy dark hair and the little black eyes filled with somnolence and accusation. But Rea is playing an Ulster protestant, Eric, who suffers from psychotic delusions. We first meet him in a hospital when he calls his black English therapist a ‘nigger’. Then he tells his daughter she’s a ‘cunt’. I mention these words because the writer, David Ireland, seems to imagine that he can present his hero as a foul-mouthed, hate-filled knuckle-dragger and still expect us to care about him.

Eric’s delusion focuses on his newborn grand-daughter, Mary-May, who he believes has been spiritually possessed by Gerry Adams. Eric thereby feels honour-bound to murder her. It’s an ingenious notion. That two family members are genetically predestined to wipe each other out captures the crazy essence of intertribal hatred. But the theme is pursued with such distasteful brutality that it soon dwindles into juvenile sadism.

The script’s architecture is muddled and haphazard. Eric does a stand-up routine about a trip to London where he discovers his repressed bisexuality. Back in Ulster he’s kidnapped by a comedy terrorist, Slim, who mistakes him for a Catholic. ‘Don’t you fucking move, you Fenian cunt,’ is Slim’s opening witticism. Long minutes of ranting twaddle ensue and the pair agree to execute the baby together. Soon the blood-soaked stage is strewn with the corpses of murdered women. Yet the timid Royal Court audience tittered nervously throughout this pointless and partisan exercise. To create a protagonist with the worst traits of any faith and to claim him as the paragon of a particular faith is not art. It’s defamation. And the show isn’t dramatic at all. It’s a mound of nonsense from which the ore of theatre might be extracted and refined by a genuine writer. Calling this a play is like calling a cow a banquet.