I came out of the flood shuddering, adjusted the lamp with shaking hands, and ran naked the last few yards to the site. Everything was as we’d left it. Scrabbling with chilled fingers, I dug away some of the spoil under which we’d buried Apple, until I came to the co-ax cables leading down from the SCR. I remembered how carefully Toad had connected them up, tightening nuts with his special spanners. Now I took hold of one in both hands and gave a big wrench. The cable held. I cleared more of it, right down to its junction with the black case, and heaved again, so hard that the whole device shifted, and pieces of spoil tumbled down the front of the heap.

Again I was on the verge of panic. Nothing on earth would persuade me to go back and search for the bolt-cutters again. One last effort: a colossal jerk, and away the cable came, so suddenly that I hurtled back into the far wall of the tunnel, grazing my right shoulder.

I stood shaking, more from fright now than from cold. At least the effort of struggling with the cable had warmed me up.

‘Right, you fucker,’ I said out loud to the bomb. ‘That’s you knackered.’

Into the water again. This time the same breathing technique got me through without swallowing any sludge. By sod’s law, I expected to tread on the bolt-cutters, now that I no longer needed them, but I missed them again. Back at my clothes, I looked at my watch and found I had ten minutes to make the rendezvous. I towelled off furiously, got dressed, stuffed the sodden towel into my day-sack and hauled myself up the ladder, pausing with my head out the top of the shaft to make sure that everything was clear. Finally I slipped two new padlocks into position, wrapped the old ones in the towel, and crept out of the courtyard into the street.

The wide embankment was clear of cars and pedestrians. I nipped across the road, threw the old locks into the river, and hurried back to the far pavement. I was still walking towards the mouth of the alleyway when Sergei’s car came towards me; but by then I was a safe distance from the church.

All the way back to Balashika I was uncomfortably aware that I stank like a sewer rat. But Sergei made no comment, and when I paid him off at the barrack gate I gave him twenty dollars over the odds, so that he went off in high good humour.