The rest of Blue team quickly came across, Whinger last. He gave me a strained look, but never said a word about the setback – just a quick ‘Idyom!’ to his guys, and they were gone, round the end of the lift-housing to the point where the emergency stairs reached the roof.

I led the two surviving members of Red team along the roof to the far end and round the corner, until we were positioned above the target windows. There we quickly laid out our ropes. We found ideal anchor-points in the form of a strong metal rail that skirted the raised top of the lift shaft, and in a couple of minutes we were ready to descend.

‘Red leader,’ I called. ‘Can I have a sniper report on the windows? Are all curtains drawn?’

Anna instantly passed the request. I heard Green come in: ‘Da, da. Vsyo,’ and in a second I got, ‘Yes, all curtains closed.’

My watch said 9.24. ‘Red leader,’ I reported. ‘Starting descent now.’

Abseiling down a building in the dark is never a picnic. Still less is it easy in a high wind. The longer your rope, the more you swing about, and the greater the danger of accidentally bumping against a window. But it was no good pissing about. I stuck my arse into space, walked backwards over the edge of the roof, and started down.

Luckily the shape of the building was kind to us. All the doors and windows were set back about a metre inside the balconies, so that as we came past each floor there was very little chance of any accidental contact with the inner wall of the building.

Inches at a time I tip-toed down the wall and dangled in space above the top half of the first balcony. On down past the metal rails. Sixteen done. Fifteen the same. Slowly on past fourteen. My two guys were doing OK, to the right and left of me. Between fourteen and thirteen a terrific gust of wind swung us so violently that all three of us bumped against each other. Luckily the windows were closed and curtains drawn all the way down, courtesy of the wild night.

My boots touched the top rail of the twelfth-floor balcony. I eased myself down gently until my backside was on the rail, then got my feet on the floor of the balcony itself. I’d landed in front of Window Two. The greenish curtains were drawn tight, but light was shining out round the edges.

The second I was out of my ropes I turned to guide Igor in.

By 9.28 all three of us were in our prearranged positions: myself crouching beside the door, Nikolai on my right, Igor on my left. Even in the relative shelter of the balcony the wind was blustering loudly, and there was no need to keep my voice down when I reported in. ‘Red leader, on target. Blue, report your state.’