'I know that part of him,' Helen said, 'rather well. George hated being asked what he was thinking about. He'd shut you up at once, and go very cold. But then it's a silly thing to ask people, isn't it? It's an invitation to a lie.'

I watched the man over there.

'I never knew,' Willi said, 'that he carried a gun. It surprises me.'

The girl came to the table and he asked for another schnapps; Helen and I passed. The man had come in alone and was talking to someone near the stage. 'Willi,' I said, 'did George ever meet your girlfriend, Inge?'

'Yes.'

'Did he show any interest in infiltrating the Faktion?'

'Infiltrating…'

'In getting closer to them.'

'He was – how will we put it? – like a moth at a flame. And I thought that was not good for him, as a member of the British Embassy and everything. He had an official position, and I thought he might be in danger of – of compromising himself. So I stopped telling him anything about the Faktion.'

The man was asking for a girl, I saw now, and one of them slipped off the high stool at the bar and went across to him.

'You stopped telling George about the Faktion' I said to Willi. 'So what had you told him already?'

He drew on his cigarette immediately, looking down, squinting against the smoke. 'Oh, various things. Things that Inge had told me.' With a slight shrug – 'I miss her, you know. She was… good-looking, yes. You have seen Mai Britt? She is -'

'Important things, Willi?'

'What?'

'Had you been telling George Maitland important things about the Faktion?'

Cigarette. In a moment, 'I do not think so.'

The girl was taking the man through the black velvet curtains. There was only the slightest chance in any case that we'd been followed here. I'd checked the environment with extreme care when we'd got into the cab outside the Cafe Brahms; the black Mercedes hadn't been in sight: not that one, with the three-pronged antenna on the boot.

The waitress brought Willi's drink.

'Schnapps, darling.'

'Danke.'

He raised his glass, and I nodded. Helen wasn't looking. She was watching the girls perched at the bar, their white spindly arms angled, hands on hips, their long legs reaching from their brief silk slips. Two of them had bruises on them. As Helen watched them she stroked her cheek against the soft lambswool collar of her coat.

I leaned nearer Willi. 'You see, I'll be glad to help you fetch your things from your flat, as I said, as long as you do your bit. What, for instance, was the most important thing you told Maitland about the Rote Armee Faktion?'

He shifted on his chair. 'I stopped telling him anything at all,' he said with a trace of impatience. 'I even stopped seeing my girlfriend. I tried to wean her away from those people, but she was too involved. It excited her, you understand. So I stopped seeing her. It's all… finished with now.' He brought his eyes back to mine at last, but it wasn't easy.

I spoke quietly. I didn't think Helen was listening any more; she was watching the velvet curtains now, stroking her cheek against her collar. 'Willi,' I said, 'I'm afraid it's not all finished with now. Since George was murdered, "those people" mounted surveillance – put a watch on the house where our gentle friend here is living, and they put a watch on your flat, as you know, and when you left there tonight they had two men tracking you – at least two, possibly more. And you're now cut off from your home and your normal life and I have to tell you, Willi, that unless you earn my protection you may well follow your friend George Maitland in a matter of days, even a matter of hours. I would've thought this much would be clear to you, and I'm sorry to have to spell it out, but it could in fact save your life.'

I sat back and drank some tonic; it was getting warm in this place, but that wasn't why there were drops of sweat forming on Willi's forehead. I glanced at Helen; she was still absorbed by the girls. One of them had noticed it, and was returning her gaze steadily, her long thin fingers playing with her cigarette holder.

I looked back at Willi. 'It's getting late,' I said. 'I've come a long way to see you, and for your own sake I want it to be worth while.'

'It is difficult,' he said, and crushed his cigarette out in the black onyx bowl and took another one from the packet, his hands moving with the speed of a conjuror's, the sweat giving his forehead a sheen below the blond thinning hair. 'Already I am being followed, and I have done very little. What will happen if I reveal things to you, and they find out?

'They won't find out.'

'But you cannot guarantee that.' Flicking his lighter, his pale face bright, suddenly, his eyes strained – They may capture you.'

'I've never talked yet.'

They are vicious,' he said urgently, those people. I know this.'

'Of course. They're terrorists.' I leaned close to him again across the little table. 'You'll be much safer, Willi, if you trust me and let me help you, than if you walk out of here on your own tonight. Where can you go? I'm used to this kind of thing, Willi; It's my job, and I know how to handle it. For you it's very different. We're sitting here tonight talking about George Maitland. I don't want to be sitting with Helen somewhere in a couple of days' time talking about Willi Hartman.'

Pulling on his black cigarette, his hands on the move the whole time, his eyes darting everywhere, seeing nothing. I was sorry for him. He'd taken up with a very good-looking girl and suddenly he'd found himself on the fringe of a very nasty set and before he could pull out they were on to him. If I hadn't felt sorry for him I would have given him the message a lot less gently than I had – either talk or get out and duck when you hear the shots, so forth.

'The Faktion,' he said at last, 'has set up an operation, and they call it Nemesis.' He'd got the message all right, and I began listening carefully. 'The object of this operation is to place a bomb on board an international flight scheduled by one of the major US airlines. I do not know which airline, or which flight.'

Oh my God. In a moment I asked him, 'Have they got a mule lined up?'

'I don't know. There is never any problem with that; they will be using a Semtex bomb, obviously, and they can persuade almost any passenger to take it on board concealed in a suitcase or something like that; it's what they did with Pan Am Flight 103; they just got a girl to take it on board with her.' The sweat was bright on his forehead and he got out his handkerchief.

'You know more than that, Willi.'

His eyes widened. 'But I swear to you -'

'What's their timing for this? Were they – was Inge talking about days, weeks, when you last spoke to her?'

'She said nothing about -'

'You must have got an idea, Willi. Did it sound as if they were getting near the deadline? Did Inge sound excited about it?'

'Yes, yes, she did, but that was the way she always sounded when she talked about the Faktion. She -'

'But I'll bet she was as high as a kite about this one, Willi, I mean she wasn't talking about just another financier in a Mercedes like Herrhausen or just another judge in a restaurant like Soderheim, she was talking about another Lockerbie, wasn't she, Willi, you'll find you can remember more than you think you do, so keep on trying.'

If he was telling the truth and if Inge hadn't been selling him a line to make herself look big I was going to have to send a signal to London tonight that I didn't want to, that I very much didn't want to. The ghost of Lockerbie had started walking again.

Willi was sitting with his eyes squeezed shut, pinching the bridge of his nose. 'I remember Inge said something about waiting for a passenger list, a certain passenger list.'