He blew evil-smelling cigar smoke. 'It's a pleasure to do business with you, Samson. You make everything very clear.'

'So let me make this clear too. If you try to turn me round, if you try any tricks at all, I will blow you away.'

By midday we'd been waiting nearly three hours, and our plane had still not arrived. Other departures were also delayed. The official explanation was the hurricanes. Mexico City airport was packed with people. There were Indian women clasping sacks of flour and a sequin-suited rock group guarding their amplifiers. All found some way to deal with the interminable delay: mothers suckled babies, boys raced through the concourse on roller-skates, a rug pedlar – burdened under his wares – systematically pitched his captive audience, tour guides paced resolutely, airline staff yawned, footsore hikers snored, nuns told their rosaries, a tall Negro – listening to a Sony Walkman – swayed rhythmically, and some Swedish school kids were gambling away their last few pesos.

Dicky Cruyer had excess baggage, and some parcels of cheap tin decorative masks that he insisted must go as cabin baggage. From where I sat I could see Dicky focusing all his charm on to the girl at the check-in desk. There were no seats available so I was propped on one of Dicky's suitcases talking to Werner. I watched Dicky gesturing at the girl and running his hands back through his curly hair in the way he did when he was being shy and boyish.

'Don't trust him,' said Werner.

'Dicky? Don't worry, I won't.'

'You know who I mean,' said Werner. 'Don't trust Stinnes.' Werner was sitting on another of Dicky's many cases. He was wearing a guyavera, the traditional Mexican shirt that is all pleats and buttons, and with it linen trousers and expensive-looking leather shoes patterned with ventilation holes. Although Werner complained of Mexico's heat and humidity, the climate seemed to suit him. His complexion was such that he tanned easily, and he was more relaxed in the sunshine than ever he'd seemed to be in Europe.

'There's nothing to lose,' I said.

'For London Central, you mean? Or nothing to lose for you?'

'I'm just doing what London want me to do, Werner… Theirs not to make reply, Theirs not to reason why, Theirs but to do and die… You know how London expect us to work.'

'Yes,' said Werner, who'd had this same conversation with me many times before. 'It's always easier to do and die than it is to reason why.'

'I don't trust him; I don't distrust him,' I said as I thought about Werner's warning. 'I don't give a damn about Stinnes. I don't begrudge him his opportunity to squeeze a bigger cash payment from the department than any loyal employee ever got. More money, I'd guess, than the wife and kids of any of the department's casualties ever collected. But it makes me wonder, Werner. It makes me wonder what the hell it's all about.'

'It's the game,' said Werner. He too was slumped back against the wall with a plastic cup of warm, weak coffee in his hand. 'It's nothing to do with virtue and evil, or effort and reward; it's just a game. You know that, Bernie.'

'And Stinnes knows how to play it better than we do?'

'It's not a game of skill,' said Werner. 'It's a game of chance.'

'Is there nothing that lights up and says "tilt" when you cheat?'

'Stinnes isn't cheating. He's just a man in the right place at the right time. He's done nothing to entice London to enrol him.'

'What do you make of him, Werner?'

'He's a career KGB officer. We've both seen a million of them. Stinnes holds no surprises for me, Bernie. And, providing you don't trust him, no surprises for you either.'

'He didn't ask enough questions,' I said. 'I've been thinking of that ever since the boat trip. Stinnes didn't ask me any important questions. Not the sort of questions I'd be asking in his place.'

'He's a robot,' said Werner. 'Did you expect him to engage you in a political argument? Did you expect a detailed discussion about the deprivation of the Third World?'

'I suppose I did,' I admitted.

'Well, this is the right country for anyone looking for political arguments,' said Werner. 'If ever there was a country poised on the brink of revolution, this is it. Look around; two-thirds of the Mexican population – about fifty million people – are living at starvation level. You've seen the campesinos struggling to grow crops in volcanic ash or rock, and bringing to market half a dozen onions or some such pathetic little crop. You've seen them scratching a living here in the city in slums as bad as anywhere in the world. Four out of ten Mexicans never drink milk, two out of ten never eat meat, eggs or bread. But the Mexican government subsidizes Coca Cola sales. The official explanation is that Coca Cola is nutritious.' Werner drank some of the disgusting coffee. 'And, now that the IMF have forced Mexico to devalue the peso, big US companies – such as Xerox and Sheraton – can build factories and hotels here at rock-bottom prices, but sell to hard-currency customers. Inflation goes up. Unemployment figures go up. Taxes go up. Prices go up. But wages go down. How would you like it if you were Mexican?' It was quite a speech for Werner.

'Did Stinnes say that?'

'Haven't you been listening to me? Stinnes is a career RGB officer. Stinnes doesn't give a damn about the Mexicans and their problems, except how and when it affects his career prospects. I started talking about all this to him at the club one evening. Stinnes knows nothing about Mexico. He's not even had the regular briefing that all East European diplomatic services give to their personnel.'

'Why?' I said.

'Why? said Werner irritably, thinking I merely wanted to change the subject. 'How could I know?'

'Think about it, Werner. The first thing it indicates is that he came here at short notice. Even then, knowing the KGB, they would have arranged for him to have political indoctrination here in Mexico City.'

Werner shifted his weight uncomfortably on Dicky's suitcase and looked around to see if there was anywhere else to sit. There wasn't; in fact the whole place was getting more and more crowded. Now there was a large group of young people carrying bright orange shoulder-bags that announced them to be a choir from New Zealand. They were seating themselves all along the corridor. I hoped they wouldn't start singing. 'I suppose you're right,' said Werner.

'I am right,' I said. 'And I'll tell you something else. The complete absence of political indoctrination suggests to me that Stinnes is not here to run agents into California, nor to supervise Biedermann's funnelling of Moscow money to local organizations.'

'Don't keep me in suspense,' said Werner wearily.

'I haven't got the answer, Werner. I don't know what Stinnes is doing here. I don't even know what I'm doing here. Stinnes could be positively identified without having me along.'

'London didn't send you along so that you could identify Stinnes,' said Werner. 'London sent you along so that Stinnes could identify you.'

'No anagrams, Werner. Keep it simple for me.'

'What do you think was the first thing that came into his mind the other night when I started telling him about freezers, videos and the acceleration a Porsche 924 turbo gives you from a standing start?'

'Entrapment?'

'Well, of course. He was terrified that I was a KGB employee who was going to provide the evidence that would put him into a Siberian penal battalion for twenty years.'

'Ummm. But he could be sure that I was an SIS agent from London because he'd actually had me under arrest in East Berlin. I suppose you're right, Werner. I suppose Bret had that all figured out.'

'Bret Rensselaer, was it? Of all the people in London Central he's the most cunning one. And right now he's very keen to prove the department needs him.'