The Contingency Plan, Bush Theatre, London

Is this the way the world will end, or at least our bit of it? In two plays under one roof – On the Beach and Resilience – the playwright Steve Waters combines the satirical scariness of J G Ballard with the silken argufying of Bernard Shaw or David Hare: it's a total bust as the Antarctic glaciers melt and Skegness is threatened with extinction.

Plays about climate change sound as appetising in theory as a film on the subject by Al Gore, or yet another column by George Monbiot, but the good thing about these plays is that they take an apocalyptic line while allowing for scepticism. As one of Dave's appointments in a future Conservative cabinet says, "there's something festive about a national catastrophe."

It's that same minister who fears the Trojan Horse effect of climate change as a fast track to a nanny state, but you do feel by the end that alarmist glaciologists deserve better than to be told to go back to their penguins.

Waters's hero, Will Paxton, is a government adviser who advocates chilling proposals that would indeed still only amount to a contingency plan: compulsory purchase of inland areas, the conversion of East Anglia to wetland as a protective sump, and the demolition of all houses that are not carbon neutral. Oh, and one car per street.

In the first of the two two-hour plays, Will's father, also a glaciologist, but one who has retired from the fray to study the birdlife in Norfolk, inhabits a house using only four tons of carbon a year. He and his wife, Jenny, keep no precooked or packaged food, and they even boil the toxins out of the sea-kale they consume with the local fish.

How all of this, or Dave riding a bike, or you and me not going on package holidays, will save the planet is not entirely clear, but Will's dad's way of dealing with the inevitable is to block the roads, breach his own defences and pretend nothing's happening. As a metaphor, it's truly more alarming than the reality of a tsunami that's about to wipe out Bristol.

These desperate oldsters-on-the- edge are played brilliantly by Robin Soans and Susan Brown, who return from the dead 72 hours later in the second play as a government scientific advisor, and a sleek Minister for Resilience called Tessa (quite Jowelly). They are joined at the top table by Geoffrey Streatfeild as Will, trying to shake ministers out of their complacency over taking low-carb holidays in Dorset.

The Minister for Climate Change, Christopher Casson (David Bark-Jones), has been holidaying under canvas. But Cleethorpes will soon be under water and Essex will soon be evacuated. And London? "I'd have thought Muswell Hill could sit tight," says cheery Chris, who evinces rather less concern about Cromer or Yarmouth, next on the climate's hit list.

The theatre has suddenly woken up to these issues, quicker, perhaps, than the rest of us, and these superbly acted productions by Michael Longhurst and Tamara Harvey had the unexpected effect of making me want to send off for a few brochures on long-term holiday excursions to the moon.

To 6 June (020 8743 5050; www.bushtheatre.co.uk )