‘All the passport staff at Britain’s seaports and airports who have been on duty since Quoit disappeared have been interviewed. Flight lists of all airlines have been checked; the flight crews of almost all aircraft on which anyone remotely fitting his description has travelled, and, likewise, all ferry staff, have been interviewed. No one has seen him. And yet he is an unusual-looking man, a distinctive man, a man whom, once seen, is never forgotten, and yet no one saw him. That in itself is no proof at all – thousands of flights and boats leave this country every hour – but I have an Intelligence report from Moscow that seems to tie in with this.

‘Someone is going to be smuggled out of England next Monday, on the 10.00 a.m. Aeroflot flight to Moscow. Our contact does not know who this person is, but believes he is either a scientist or has detailed knowledge of certain scientific advances in this country.’

‘Our friend could fit that bill,’ I said.

‘Very neatly indeed.’ Fifeshire relit his cigar, which was burning down one side only.

‘If we’re on the right track with our thinking, Sir Isaac has been kidnapped by the Russians. The Russians have taken him to a secret television studio somewhere in England and got him to speak. Maybe he didn’t realize it was a studio, and maybe he didn’t realize he was being videotaped. Afterwards, they dub over, in perfect lip-sync, someone who sounds very like him making a strong defection and anti-nuclear speech. Then they bang him against a back-drop of Red Square and send the tape off to the BBC. All perfectly possible, except it doesn’t make any sense. It sounds more like a prank pulled by the anti-nuclear people – the Ecologists – some group like that.’

‘Possible,’ said Fifeshire, ‘but I would have thought most unlikely.’

I nodded, and lit a cigarette.

The Honourable Violet-Elizabeth Trepp produced coffee. It was the colour of tea made with a five-year-old tea bag, and tasted like paraffin. Fifeshire waited until she had left, then poured his into an ornate pot containing a rubber plant. ‘She doesn’t understand why none of my plants ever live more than a few weeks,’ he said, then continued.