Chains of Dew, Orange Tree Theatre, London

Once again, the Orange Tree has unearthed a fascinating rarity. Written in 1919 in protest at the Cornstock Law, which forbade the circulation of "obscene" documents on birth control, Chains of Dew hasn't been performed since its premiere in 1922.

Its American author, Susan Glaspell, was a founding member of the legendary Provincetown Players, which helped to launch Eugene O'Neill. In her day likened to Shaw and Ibsen, she has fallen into neglect. Kate Saxon's captivating revival of this unpublished play reveals Glaspell's gift for trenchant and delightful comedy. Vividly evoking the era of bobbed hair and birth-control activism, the piece combines polemical punch with a giddy screwball quality.

At the centre of proceedings is the banker/poet Seymore Standish. On trips to New York, he hobnobs with progressive types and writes verse. Back in his Midwestern hometown, he's a golf- and bridge-playing pillar of the community. He makes out that he'd be a great poet if only he could shed the shackles of bourgeois respectability. The amusing scenes detailing his domestic set-up belie this claim. His wife Diantha, whom he patronisingly calls Dotty, is no fool and nurses a desire for change that, unlike his, is genuine, while his mother creates rag dolls that are, though unrecognised as such, subversively satiric portraits of their censorious neighbours.

Glaspell engineers a collision between the reactionary Midwest and East Coast liberalism when Nora Powers, a bobbed zealot for birth control, descends on the town for a campaigning visit. The name suggests a link with Ibsen and the Shavian life force, but, as Ruth Everett's winning performance indicates, there's also a mischievously madcap charm in her assurance. Seymore (a lovely comic portrayal of two-faced self-interest from David Annen) harbours sexual desire for Nora but deplores her influence on his wife (the excellent Kate McGuinness), who, in a whirl of emulative liberation, has her hair bobbed and cancels stuffy social engagements.

Her behaviour calls Seymore's bluff and exposes the fact that, in this play, the truly radical impulses emanate from the women. Rather than offer false uplift, though, Glaspell dramatises the pressures that would push such a wife back into reluctant conformity – the incisive comedy all the more powerful for the note of bitter realism on which it ends.

To 26 April (020-8940 3633)