Henna night is not a title to dye for. It sounds more like a case of Kathy Lette syndrome. But Amy Rosenthal's captivating 50-minute two-hander offers better reasons for its moniker than a bad pun. In certain Eastern societies, a bride has her hair dressed with henna on the eve of her wedding by a woman who has found happiness. When one of the white girls here reads out that information from the side of the packet, it causes a frisson of embarrassment, for the situation in which this pair find themselves could be seen as a painful travesty of that ritual.

Dumped by the unseen Jack, Judith (Amy Marston) leaves a tragic phone message, manipulatively hinting at both pregnancy and suicide. But instead of the expected mercy dash from her ex, she receives a visit from his new partner, Ros (Rosie Thomas). The water has gone off just as Judith's embarked on a DIY henna treatment. So the only advantage she has over her supplanter is a moral one, if that.

You may be expecting a drama in which the two rivals edge toward sisterhood and end up washing that man right out of their hair. In Caroline Hadley's appealing and well-acted production, you get something more truthful. Sure, the play has some of the flaws you'd expect from a newcomer. The gag lines are good but they come so thick and fast that the dialogue seems to express authorial jitters. Henna Night gradually and skilfully reveals two very different women who could, in other circumstances, have been good friends. Rosenthal resists the opportunity for bogus uplift. Indeed she has Judith tell her visitor that making her like her is perhaps the only bad thing Ros has done.

Two gabby Northern schoolgirls share a bloke in an altogether fuller sense in Rita, Sue and Bob Too. As an "extra" for babysitting, they are shagged by a handyman in the back of his car. At the Soho Theatre, before an extensive tour, Max Stafford-Clark revives his superlatively acted Out of Joint production of Andrea Dunbar's candid, comic, grim yet vital portrait of life on a Bradford housing-estate in 1982. It is coupled once again with Robin Soans's excellent A State Affair, which revisits the area 18 years on and is assembled from interviews with the residents. The big difference is that, in 1982, there were still the vestiges of community. In 2000, the working class has become a heroin-ravaged underclass, and the place an urban hell.

All the pitfalls – voyeurism, sermonising, sentimentalising its portrait of the do-gooding insiders who struggle to make a difference – are avoided. While there is no false optimism in the energy of Stafford-Clark's masterly production, it refuses to be driven to the easy option of despair. It's not just as a bracing antidote to the mindless materialism of Christmas that this double bill has strong claims to be the best show in town.

To 22 Dec, 020-7352 1967 / 12 Jan, 020-7478 0100