If you remember the Eighties, you probably remember Protect and Survive – a notoriously grim government pamphlet telling citizens what to expect during a nuclear war. This intelligently-constructed play recreates some of that Cold War terror, and reminds us of a truth we seem in danger of forgetting: that there are still weapons against which we cannot protect, and wars which we cannot survive.

The horror of the hydrogen bomb would be impossible to recreate on stage, and Protect and Survive is wise enough not to try. Instead, very cleverly, we see the recording of a radio play; unashamedly modelled on genuine TV dramas like The War Game and Threads, the story surrounds the collapse of civilisation in the aftermath of nuclear war. As the actors gather round microphones, they rehearse selected scenes from their performance scripts – a gambit which offers playwright Jonathan Williamson the perfect licence to skip to the darkest moments in his plot.

It also provides an excellent excuse for some shameless exposition, as director Cat – under the guise of briefing her actors – fills us in on exactly how radiation poisoning eats the human body from inside. This has to rank as one of the smartest devices I've ever seen at the Fringe, and on the whole it works remarkably well – although there were a handful of occasions when I felt Cat's interjections interfered with, rather than contributing to, the action on stage.

The scenes we see are uncompromising, and powerfully delivered by a uniformly compelling cast. Even though this is notionally a radio play, there's enough physicality to maintain our interest, and to capture the increasing brutality as society degenerates from brutal martial law to unrestrained feral disorder. It's all interspersed with genuine quotes from the original Protect and Survive public information films – a periodic warning that what we're seeing is not a fanciful horror story, but a realistic scenario our country once prepared for.

So it's surprising to note that Protect and Survive is also a witty, enjoyable show. The key to that lies again in the clever concept: because we're watching a play being recorded, we get to see the actors bantering, squabbling, and occasionally snogging between scenes. The observations and the thespian in-jokes are very sharp indeed, and the (real) actors all draw their (fictional) characters with enough detail to make us care. It all adds up to a counterpoint to the bleakness, a continual reminder of the flawed but vibrant world a nuclear war would destroy.

A year ago, you might have questioned the value of resurrecting this distant slice of Cold War history; but with bellicose rhetoric increasing across the Atlantic, it doesn't feel so distant any more. Referring to Threads, Neil Kinnock once said that the story of a post-nuclear society needs to be told time and time again. This particular telling is a worthy response to that still-relevant call.