The Dornier lurched again and my head rolled on the protective woolly band. Dex was swinging us left and right. This time I didn’t want to look out of the window in case I saw why.

It could be that we were weaving between the tower blocks. I pictured the local kids’ faces pressed against their bedroom windows, wondering what the fuck was going on. Red Ken said that was what had happened last time. Dex had stuck a torch under his chin, Hallowe’en style, and given them a wave. They were probably still having nightmares.

The Berlin Wall was intact, but only just. It still boasted mines, dogs, electric fences, machine-guns on fixed arcs, everything the Communist regime needed to stop its citizens leaking West, but nowadays even the guards wanted to jump ship. Everybody knew it would be over very soon, one way or another. Only a year ago, Ronnie Reagan had stood at the Brandenburg Gate and delivered his ‘If you seek peace, Mr Gorbachev, open this gate! Tear down this wall!’ speech. But for now they were still the bad guys – and Dex and the three of us under Red Ken’s command were about to cross into their airspace.

My headphones crackled as Dex quipped: ‘Not far now, chaps – home for tea and wads before first light, what?’

The aircraft plunged to rooftop height. He gave a little chuckle. ‘You can cross radar off your worry list – I think we bought that last week.’ The chuckle became a laugh. ‘If not, I hope you’re wearing sensible shoes. It’s a long walk home.’

As if the bone jokes weren’t bad enough, Dex treated us to the first few lines of his old school song. His cut-glass accent provided the icing on the whole SOE cake. ‘“Jo-lly boat-ing weather, /And a hay har-vest breeze, /Blade on the fea-ther,/ Shade off the trees…”’