'A drink, Werner?' said Rudi.

'No thanks.' Although Werner's tone showed no sign of impatience I felt bound to leave.

Werner was another one who wanted to believe I was in danger. For weeks now he'd insisted upon checking the street before letting me take my chances coming out of doorways. It was carrying caution a bit too far but Werner Volkmann was a prudent man; and he worried about me. 'Well, goodnight, Rudi,' I said.

'Goodnight, Bernd,' he said, still looking at the stage. 'If I get a postcard from Lange I'll let you put the postmark under your microscope.'

'Thanks for the drink, Rudi.'

'Any time, Bernd.' He gestured with the cigar. 'Knock louder. Maybe Lange is getting a little deaf.'

Outside, the garbage-littered Potsdamerstrasse was cold and snow was falling. This lovely boulevard now led to nowhere but the Wall and had become the focus of a sleazy district where sex, souvenirs, junk food and denim were on sale. Beside the Babylon 's inconspicuous doorway, harsh blue fluorescent lights showed a curtained shop window and customers in the Lebanese café. Men with knitted hats and curly moustaches bent low over their plates eating shreds of roasted soybean cut from the imitation shawarma that revolved on a spit in the window. Across the road a drunk was crouching unsteadily at the door of a massage parlour, rapping upon it while shouting angrily through the letter-box.

Werner's limp was always worse in the cold weather. His leg had been broken in three places when he surprised three DDR agents rifling his apartment. They threw him out of the window. That was a long time ago but the limp was still there.

It was while we were walking carefully upon the icy pavement that three youths came running from a nearby shop. Turks: thin wiry youngsters in jeans and tee shirts, seemingly impervious to the stark cold. They ran straight at us, their feet pounding and faces contorted into the ugly expressions that come with such exertions. They were all brandishing sticks. Breathlessly the leader screamed something in Turkish that I couldn't understand and the other two swerved out into the road as if to get behind us.

My gun was in my hand without my making any conscious decision about needing it. I reached out and steadied myself against the cold stone wall as I took aim.

'Bernie! Bernie! Bernie!' I heard Werner shout with a note of horrified alarm that was so unfamiliar that I froze.

It was at that moment that I felt the sharp blow as Werner's arm knocked my gun up.

'They're just kids, Bernie. Just kids!'

The boys ran on past us shouting and shoving and jostling as they played some ritual of which we were not a part. I put away my gun and said, 'I'm getting jumpy.'

'You over-reacted,' said Werner. 'I do it all the time.' But he looked at me in a way that belied his words. The car was at the kerbside. I climbed in beside him. Werner said, 'Why not put the gun into the glove compartment?'

'Because I might want to shoot somebody,' I said, irritable at being treated like a child, although by then I should have become used to Werner's nannying. He shrugged and switched the heater on so that a blast of hot air hit me. We sat there in silence for a moment. I was trembling, the warmth comforted me. Huge silver coins smacked against the windscreen glass, turned to icy slush and then dribbled away. It was a red VW Golf that the dealer had lent him while his new BMW was being repaired. He still didn't drive away: we sat there with the engine running. Werner was watching his mirror and waiting until all other traffic was clear. Then he let in the clutch and, with a squeal of injured rubber, he did a U-turn and sped away, cutting through the backstreets, past the derelict railway yards to Yorckstrasse and then to my squat in Kreuzberg.

Beyond the snow clouds the first light of day was peering through the narrow lattice of morning. There was no room in the sky for pink or red. Berlin 's dawn can be bleak and colourless, like the grey stone city which reflects its light.

My pad was not in that part of Kreuzberg that is slowly being yuppified with smart little eating places, and apartment blocks with newly painted front doors that ask you who you are when you press the bell push. Kreuzberg 36 was up against the Wall: a place where the cops walked in pairs and stepped carefully over the winos and the excrement.

We passed a derelict apartment block that had been patched up to house 'alternative' ventures: shops for bean sprouts and broken bicycles, a cooperative kindergarten, a feminist art gallery and a workshop that printed Marxist books, pamphlets and leaflets; mostly leaflets. In the street outside this block – dressed in traditional Turkish clothes, face obscured by a scarf – there was a young woman diligently spraying a slogan on the wall.

The block in which I was living had on its facade two enormous angels wielding machine guns and surrounded by men in top hats standing under huge irregular patches of colour that was the under-painting for clouds. It was to have been a gigantic political mural called 'the massacre of the innocents' but the artist died of a drug overdose soon after getting the money for the paint.

Werner insisted upon coming inside with me. He wanted to make sure that no unfriendly visitor was waiting to surprise me in my little apartment which opened off the rear courtyard. 'You needn't worry about that, Werner,' I told him. 'I don't think the Department will locate me here, and even if they did, would Frank find anyone stouthearted enough to venture into this part of town?'

'Better safe than sorry,' said Werner. From the other end of the hallway there came the sound of Indian music. Werner opened the door cautiously and switched on the light. It was a bare low-wattage bulb suspended from the ceiling. He looked round the squalid room; the paper was hanging off the damp plaster and my bed was a dirty mattress and a couple of blankets. On the wall there was a tattered poster: a pig wearing a policeman's uniform. I'd done very little to change anything since moving in; I didn't want to attract attention. So I endured life in this dark hovel: sharing – with everyone living in the rooms around this Hinterhof – one bathroom and two primitive toilets the pungent smell of which pervaded the whole place. 'We'll have to find you somewhere better than this, Bernie.' The Indian music stopped. 'Somewhere the Department can't get you.'

'I don't think they care any more, Werner.' I looked round the room trying to see it with his eyes, but I'd grown used to the squalor.

'The Department? Then why try to arrest you?' He looked at me. I tried to see what was going on in his mind but with Werner I could never be quite sure.

'That was weeks ago. Maybe I've played into their hands. I've put myself into prison, haven't I? And they don't even have the bother or the expense of it. They are ignoring me like a parent might deliberately ignore some child who misbehaves. Did I tell you that they are still paying my salary into the bank?'

'Yes, you told me.' Werner sounded disappointed. Perhaps he enjoyed the vicarious excitement of my being on the run and didn't want to be deprived of it. They want to keep their options open.'

'They wanted me silenced and out of circulation. And that's what I am.'

'Don't count on anything, Bernie. They might just be waiting for you to make a move. You said they are vindictive.'

'Maybe I did but I'm tired now, Werner. I must get some sleep.' Before I could even take my coat off a very slim young man came into the room. He was dark-skinned, with large brown eyes, pockmarked face and close-cropped hair, a Tamil. Sri Lanka had provided Berlin 's most recent influx of immigrants. He slept all day and stayed awake all night playing ragas on a cassette player. 'Hello, Johnny,' said Werner coldly. They had taken an instant dislike to each other at the first meeting. Werner disapproved of Johnny's indolence: Johnny disapproved of Werner's affluence.