“Not everyone can be all right. That isn't how things work.” The two characters in Chloë Moss's heartrending new play are engaged in an exhausting battle with that brutal piece of advice, passed off as homespun wisdom and callously handed out to one of them when she was a child. Commissioned by Clean Break, the company that works with women affected by the criminal justice system, and created after a research period at Cookham Wood prison, the piece is beautifully written: comic, colourful, full of pain and tenderness and truth. And Lucy Morrison's production has a poignant and powerful lucidity.

Marie (Cathy Owen) is struggling to rebuild her life after release from prison. The arrival on her doorstep of Lorraine (Jan Pearson), an older woman who was her best friend inside, throws all her efforts into disarray. The pair's co-dependent relationship is as emotionally disorientating as the secret, shameful nostalgia that Marie feels for her time behind bars. The connection between them, in which the roles of mother and child are interchangeable, is comforting yet uncomfortably close.

Moss's flair for dialogue and characters that are both quirky and utterly authentic is served with terrific verve here. Pearson's Lorraine, artificially cheery and loudly gallumphing, invades Marie's flat and existence with a wilful ignorance born of desperate fear and loneliness. As Marie, Owen's face is hardened by suffering; hounded by Lorraine's neediness and the misery she represents, she flees into the shower, where she crumples to the floor, a prisoner once again in its glass cubicle. As they wrestle with the torments of the past and their terror of the future, they reveal flashes of dangerously violent unpredictability.

Moss often illuminates moments of quiet tragedy with a sense of the absurd: Lorraine describes how the cellmate who succeeded Marie “tried to do herself in with a knee- length sock”. And in the incidental details of the women's conversations, we glimpse the string of disappointments that make up their histories. It's an awful irony, too, that Lorraine should be closer, and more of a maternal figure, to Marie than to her own estranged son. Both women are terrifyingly vulnerable, and Owen and Pearson's performances are unstinting in their truthfulness and commitment. Raw and riveting.

Box office: 020-7478 0100

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