A young couple leave behind the urban rat race and move to the coastal countryside. No more sweaty, besuited commute! No more office backstabbing, social one-upmanship or water-cooler trivialities. Instead, the husband imagines, an opportunity to start afresh - to live off the land, in harmony with nature, and to revive his socialist ideals. His wife pictures a domestic idyll where she'll raise golden-haired children. It's going to be perfect.

Of course, the self-deluding fantasy soon disintegrates in Torben Betts's stark two-hander, crisply directed by Adam Barnard. Barely have the couple arrived when the woman (Emily Bowker), daughter of a wealthy arms-dealer, admits in brittle cut-glass tones that at her “adequate” wedding to her working-class Brummie husband (Chris Harper) she glimpsed in her friends' eyes “a little pity”. Stripped of the distractions and anonymity of the city, they are imprisoned together in a rural isolation far from the Eden they envisaged. The vastness and implacability of the landscape are overwhelming, and the silence begins to feel like a slow death. He starts to crave booze, steaks and cinema; she turns to t'ai chi and religion. And as wind and waves gather force, apocalypse approaches.

Just over an hour long, Betts's play teases at some big existential questions: where do we find peace or salvation? Is happiness an elusive illusion? Dramatically it's terse, its characters depicted in outline rather than in detail - a characteristic mirrored in Barnard's black-box staging, in which props are drawn by the actors on to floors and walls in white marker pen, and video-projected silent-movie captions provide Brechtian scene titles.

The language, though, is compelling: a weird mix of part-contractual, part- liturgical formality, New Age platitude and pungent poetry. And the Christmas climax, with bombs falling, a storm raging and the terrified couple desperately awaiting the arrival of a guest whom they hope might be their saviour, is thunderously doom-laden. Humanity at war, nature in revolt, the wrath of a vengeful deity - whichever the cause, the end of the world is nigh. This is a skeletal play, but it's a bag of bones that leaves you truly rattled.

Box office: 020-7503 1646, to May 2

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