It’s hard to avoid thinking of today’s Szechuan when Jane Horrocks, playing Brecht’s embattled title character, declares that there’s too much misery in the province. But she’s not talking of natural disasters, which can’t be prevented by economic action, but of poverty, which perhaps can. However, this is a play in which the communist dramatist is honest enough to acknowledge the difficulty of changing the world.

Brecht’s purposeful conceit is to split his protagonist into two. At first Horrocks is Shen Te, “the angel of the slums”, a woman who, in defiance of her author’s social beliefs, was born in punishing poverty yet is instinctively generous, helpful, good. She’s given a fortune by gods who arrive, fairytale style, to search for a virtuous person. This she spends on a tobacco shop, only to be brought to the brink of ruin by the freeloaders she’s too kind to reject.

Brecht doesn’t shy from presenting the downtrodden as an ugly, unprepossessing lot, the worst of whom is Yang Sun, who professes love for Shen Te to get her to finance his career as a pilot.

All this explains why Shen Te sometimes disguises herself as her male cousin, Shui Ta, who has the ruthlessness to ensure that she herself survives to do good. It isn’t an easy transition for Horrocks, especially as she glows with warmth and naive sweetness when she’s in virtuous mode. Her voice falls an octave as she dons Shui Ta’s trousers and toughens up her body language; but it takes quite a jump of imagination to see this small, slim figure as an alpha male who terrifies mere betas.

Still, there’s no missing Brecht’s dual points, which are that a culture of need forces people to distort themselves and that we can’t rely on the gods, here a comically desperate, dilapidated lot, to solve earthly problems. I don’t know why Richard Jones, who directs, transforms the theatre into a mix of factory (sacks on conveyor belts) and arid hall. But he gets fine performances, not only from Horrocks’s Shen Te but from Adam Gillen as a fraught, distraught water-carrier and John Marquez as a Yang who starts out sleazy and ends up a sweaty, shattered opium addict.

Anyway, I left David Harrower’s brisk, crisp adaptation feeling that Brecht was far more than a doctrinaire didact. Not only does he tell a terrific story, he makes you think, really think, about the place of love and goodness in a dauntingly complex world.

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