In the base of the receiver was a small drawer containing instructions on testing, battery replacement and fault reporting, as well as how to respond to the types of message that might come through. Attack Warning Red, imminent danger of an attack. Fallout Warning Black, danger of fallout. And Attack Message White, the all-clear.

‘I don’t suppose it was ever used, except for testing.’

‘They had exercises regularly,’ said Cooper. ‘Everyone felt they had to be prepared. Or so I’m told. The ROC posts weren’t closed until 1991, after the collapse of the Soviet Union.’ He looked at Murfin. ‘Do you remember that, Gavin? You’re older than me.’

‘Are you kidding? Well, I suppose I was around in 1991, but I was more interested in Silence of the Lambs and Terminator II.’

‘I was into Sonic the Hedgehog.’

‘You’re such a baby.’

Cooper tried to imagine the awful piercing wail of the siren. The sound that had never been heard for real in the Cold War.

‘So what would you do, then?’ said Murfin suddenly.

‘What? Do when?’

‘In those last few minutes. If you knew that you had just four minutes to live, like.’

‘Blimey, I don’t know. It isn’t much time to do anything really, is it?’

‘No, you’re right. Nothing worthwhile.’ Murfin laughed. ‘It makes a joke out of all those “fifty things to do before you die” features in the papers, doesn’t it?’

‘Yes.’

Murfin thought for a moment. ‘You could pray, I suppose,’ he said.

‘I didn’t know you were religious, Gavin.’

‘Well, of course I’m not now. But if I knew I only had four minutes left to live, I might want to . . . you know, cover my options.’

‘I see.’

‘You could get quite a few “Our Fathers” in, couldn’t you? In four minutes.’

Cooper laughed. ‘I’m sure you could. But just one might be better, Gavin, if you could get the right amount of sincerity into it.’

‘Right.’

‘Or, instead of praying,’ said Murfin, ‘you could just do something you’d always really, really wanted to do, all your life, and never got the chance.’

‘Ye-es.’

They were both silent for a moment, Murfin chewing the last half of his Eccles cake, Cooper wondering how long he could resist asking the obvious question. It wasn’t long.

‘So what would that be, Gavin? The thing you’ve always really, really wanted to do, all your life?’

But Murfin shook his head. ‘I can’t tell you.’

‘Oh, go on.’

‘No way. You’d take the piss out of me, and I’d never hear the end of it back at the office.’

Cooper gazed at Murfin, watching him lick a few crumbs off his fingers and wipe them on his tie. He was wondering whether his colleague had some hidden psychological depths that he’d never suspected. What was this deep, seething urge that he daren’t even speak about?