I’d picked the right vehicle, that was clear. Nobody was going to go to much trouble to get a maroon-coloured Allegro back so I was unlikely to be seeing any police roadblocks any time soon. It was as dispiriting a vehicle inside as out: patchy grey seats and a dashboard held on with sticky tape. Whether it had left the British Leyland factory in that condition or if the owner had done it himself was anybody’s guess.

I’d calmed down a little after the initial adrenaline rush. It was well short of serenity but there was a certain kind of pragmatic numbness sloshing about in my head. It all felt a little too big to take in and I was absolutely conscious of the gaps in my knowledge. As such, I couldn’t expect to think my way to a conclusion. I simply didn’t know enough. All I could do was run through the little that I did know and try looking at it from different angles. I’d always been good at puzzles and I’ve lost count of the people who’ve told me that I’m too clever for my own good, so I took comfort in the knowledge that I was well suited to the task of working out what was going on and then what to do about it.

I broke it down into a few key pieces, writing down names on a little white pad inside my mind and then taking a virtual photograph of the page. I put the heading ‘Walt’ and underlined it with a black fountain pen in my imagination. Then I started writing.

Walter Renwick. Recruited at Cambridge, ’47. Key postings at Moscow Centre, Middle East. Damascus station chief. Time at GCHQ then back to the Service. Indiscreet critic of colonialism and capitalism. Seen as a Red sympathizer by many. Questioned hard in the wake of Philby et al. Cleared but moved sideways. Reduced interaction with Control. Given responsibility for South and Central Americas. Operation Prickly Heat, information sharing with US. Parts ways with Service in ’76. Teaching, travelling, possible private contracting work. Dec ’82, contacts former protégée, CH, offering information on war crimes taking place in Guatemala. CH instructed to take snippet of info to department head. No sale. Anonymous recording sent to Service. CH complicity, fraternizing with a subversive, making dangerous comments on direction of the West. CH permits use of country house and travels north. Intercepted by picture card from the Deck of Clubs. Told to return home ahead of debrief …

I yanked the car to the right, the windscreen filling with the big yellow back of a goods wagon. I shot a glance at the clock on the dashboard. It was pushing midnight and I was still ninety miles from Felicity and from whatever else was waiting for me back in the place where Stefan and I experienced the only gentle happiness of my whole bloody life.