Mrs. Rogers said that somebody came to the door yesterday asking about me. A man in his forties with an Irish accent. She couldn't tell what he looked like because it was dark.

She was surprised when I told her I was leaving. She said: "Leaving? Already? You've only been here three months." Actually she was wrong, it's less than that. Three months would be close to my record. She asked me if there was something wrong, some reason why I wasn't happy here. I gave her the usual story. "Got to go where the job sends me," I said. If only there was a job. That little bit of money I invested all those years ago is nearly gone now.

Considering present circumstances though, it looks like it's been enough to see me out. Who would have thought it? There wasn't much lying ahead for me. When all the money was gone I would have gone into some kind of hostel for down-and-outs, I suppose. Pretended to be mad so that I wouldn't have to provide a past. I would have survived. If I wanted to survive, that is. If I could find a reason to want to survive.

I've never seriously considered ending my life. I don't know why, it's just a biological thing probably. No living creature wants to die. Injured animals in terrible pain still fight to stay alive. The only creatures that don't fight to stay alive are human beings when that last little flicker of hope has gone. I've done pretty well, don't you think, not to have reached that point yet? I congratulate myself. There must be some kind of tiny glimmer of hope somewhere inside me or I would have stepped in front of a train years ago. I wonder where it is, that little glimmer. Why it's in there. What it's directed towards. Mysteries. There are bits of ourselves that are so deeply buried we can never get to them. Don't you think so?

I hadn't decided where to move to this time. I wondered about one of the big northern cities, or even Scotland. Then I thought, no, winter's almost here, better to move south like the birds.

Do pigeons fly south for the winter? I very much doubt it. I've never heard of a flock of migrating pigeons. Mind you, homing pigeons fly hundreds of miles, don't they? But that's to get home. That's not migration. It isn't south for the winter. I don't suppose your average city pigeon wanders very far from the same rubbish dump in its whole life

I mustn't think about pigeons so much, it upsets me.

I saw a pigeon in Whitechapel Market a few weeks ago with one of its claws completely missing. It was hobbling around on a red stump like something out of a horror film. The other claw seemed to be normal. I wonder how it lost its claw.

Pigeons. I must stop thinking about pigeons.

Did you know that when Darwin sent the manuscript of The Origin of Species to the first publisher it came back with a note saying that it was too general, and he should write something about pigeons instead? Everybody is interested in pigeons, the note said. It isn't true though, is it? You aren't interested in pigeons. I can tell. Are you even listening to me, I wonder.

I've been expecting you of course. I can't remember how long for. Thirty-five years, is it? Forty? I don't know. I don't count the years any more. What's the point?

Did Mrs Rogers let you in? Not that it matters.

You're very quiet, aren't you? Haven't you got anything to say to me? Don't you want to tell me what a bastard I am before you kill me? Don't you want to remind me of the terrible things I've done?

No? You're right, actually. There's no need. I haven't thought about much else since I was twenty years old. Since the pigeons.

I've never killed anybody with my own hands, you know. Never looked someone in the eye and pulled a trigger. Or even shot a sniper down off a roof with a rifle. I saw that happen once. It must have been 1970 or 71. The height of the Falls Road riots. There was somebody on the roof of the old corn warehouse just off the Falls. It was dark, a winter's evening, not long before Christmas. The road was full of people with guns and petrol bombs and lit torches, screaming blue murder about the sniper. He'd shot a few Catholics earlier in the day. They thought he was on that roof but they weren't sure, so they set fire to the building. They were right. It didn't take long for the smoke and the flames to get to him. He came out from wherever he was hiding and just stood there on the edge of the roof, about five stories up, with his rifle on his back, and looked down at the crowd. The flames were soaring up into the sky behind him. He didn't try to run or to jump or anything. There was a lot of excitement – people shouting "There's the fucker!" – that kind of thing – then just one gunshot, from somewhere behind where I was standing. He staggered and swayed backwards and forwards for a couple of seconds. We all thought he would fall off into the crowd, probably get torn to pieces by them, whether he was alive or not. But he didn't fall forwards. He fell backwards instead, into the flames. I'm sure it was a deliberate choice. A great big cheer went up when he fell into the fire – as if it was a football match and somebody had scored a goal. I can still hear them cheering. Wonderful entertainment, the death of an enemy.

No, in terms of bravery – or even of sophistication – what I did in the Volunteers didn't amount to anything. A schoolboy could have done it, probably done it better if he was in the science stream. Except of course for its consequences. The consequences did amount to something.

Did they tell you what my role was? I was an apprentice electrician, so they decided that I could make bombs with timers. I designed the system myself. The timer was just a little spare part for an electric oven. A thing like a wind-up alarm-clock, only instead of a bell there was a switch. You wound it up and set the clock and set the time you wanted it to go off. That was all there was to it. Let's say you set it for twelve o'clock. The switch would stay open until a second or two before twelve, then there would be a very faint click and it would close, and a bicycle-lamp battery would connect to the detonator. Then quite a lot of people would die, and some others would become crippled for life, and some more would have the skin ripped off their faces by flying glass – you know the kind of thing. An efficient and simple piece of technology.

The wind-up timers were very reliable. We bought them in small batches from regular electrical suppliers all over Ireland. We must have bought up hundreds, not just for actual bombs but for training purposes as well, and not a single one of them ever failed. They didn't cost very much either. An excellent product, for the price. Made in Taiwan, I remember.

At first we used gelignite as the explosive – heavy to carry around and not very powerful – then we got proper plastic explosives. Lighter and much more powerful. It was a bit more expensive but you got your money's worth.

That's all it was to me. A hobby, like putting model ships in bottles, only not as demanding as that. A minor technical diversion. It gave me satisfaction when they told me that one had worked. And they always worked. Simplicity was the key. Very little to go wrong. I could knock one up in half an hour, probably less. I must have made dozens of them before I saw what they did. What the actual consequences were of soldering wires onto little brass strips on bicycle-lamp batteries.

I've been a very poor host. Can I make you some tea? I think I have a few biscuits. Or would you like to kill me now?

No? Do you mind if I talk some more then? It's good to have somebody I can tell these things to – after all the years of holding on to them.

The first time I actually saw the consequences at first hand, not just sanitised pictures on TV, was the one at the covered market on Shore Street. They never told me when one of my little toys was going to be used. Everything was on a need-to-know basis, as you can imagine. I just happened on it, a couple of hours after the event. The two ends of Shore Street were blocked off with that yellow police tape, so you couldn't get very near to where it had gone off, but you could see plainly enough. The whole front of the market was demolished and the rubble was piled six or eight feet high in the road. There were cars and vans so twisted-up you couldn't tell what make they were or what colour they'd been – a lot of them were burned-out and still smoking. It looked just like the city dump out at Millfield, except that there was a group of half a dozen policemen in black uniforms going around with cameras and black bags, photographing things and then putting them in the bags. And pigeons. Hundreds and hundreds of pigeons, just like at the city dump, swarming around and pecking at things in the rubble. So many pigeons you could hardly see the rubble underneath them. All in a feeding frenzy, as if they hadn't eaten in months.

It took me a minute to work out what was going on. What it was that the policemen were putting in the bags, and what it was that the pigeons were trying to eat. I'm ashamed to tell you, but when I realised I threw up, right there at the barrier, with a whole load of people watching me. Then, damned if a few of the pigeons didn't come over and start pecking at my vomit.

The police were collecting bits of bodies of course – the smaller bits, I think they had already lifted the bigger bits – and the pigeons were helping in this... tidiness initiative. The police were trying to shoo them away, but the birds weren't paying the slightest attention. As far as they were concerned it was manna from Heaven; open season on their old tormentors the human race.

To be honest I don't know how much of it was in my head – I don't think pigeons have any special liking for raw meat, and god knows what had been in the shops and the delivery vans that were torn apart – but I did see at least some of them eat small gobbets of human flesh. It's not something that you can easily forget. I haven't been... what you might call at ease with pigeons ever since. Sometimes I have this nightmare that there are pigeons pecking out my eyes. Do you have dreams like that? Of course not, why should you?

You know what happened after the pigeons. I wouldn't like to bore you with things that you already know.

You're not going to say anything, are you? I suppose it's a bad idea to form a relationship with somebody that you're going to have to kill.

What shall I tell you then? What would you like to hear?

At the beginning it didn't seem like I was doing anything wrong. It didn't feel particularly noble or patriotic either. It just seemed like I was helping a few friends with a technical problem. Nobody questioned the cause – we just went along with it all, like you would support your local football team. Everybody I went to school with was in the Volunteers, or helping them in one way or another. I was just one more. I was a Catholic Christian Brothers boy, I wasn't taught to question. I was taught that Northern Ireland was occupied by evil foreigners, and that all the power and wealth in the country was in the hands of the Protestants, and that Catholics were oppressed and downtrodden, and the Protestants deserved everything they got. Even the priests didn't say anything different. And we had all those old rebel songs for reassurance. The ones that glorified the rising in the south in 1916.

You probably think I'm trying to justify myself. No, not really. It would be nice to be as naive as that, but of course I wasn't. Not for very long anyway. And certainly not after... the pigeons. After that I knew what it meant to blow a human being to pieces, what my little home-assembled toys actually did. It was a bit different to supporting Belfast Celtic.

After the pigeons you could say that I developed a conscience. But very little common sense to go with it. I tried to find a way out. But you don't resign from the Volunteers, as I think you know. And what difference would resigning make anyway? I had to do more than that. I had to stop them. I had to make up for some of the damage I had done – in any way that I could.

And of course there was only one way open to me. I had to go to the authorities. I had to turn informer. That's a horrible word, 'informer', isn't it? I don't know which was worse, blowing people up or getting people shot by the RUC murder squads. I suppose it depends who you ask. Which side of the fence you're sitting on. Anyway, within twelve hours of my little interview at Springfield Road RUC Station the other four people in my unit were dead, and I was sitting in another Police Station, here in London, signing for a new passport and enough money to keep me alive for three or four decades. If I was careful, that is, and I have been careful.

I've never been completely certain if the ghosts were in my head or if they were really out there, in the streets, in the cafes, behind the trees, sitting in parked cars with tinted windows. I tried not to take chances. Say nothing. Keep on the move. I haven't felt safe for a single second since 1972.

I took a few jobs at the beginning. Cash in hand labouring jobs on building sites. Things like that. Just for a bit of human contact. Then I realised I was more likely to run into people who would recognise me in that kind of setting than anywhere else. So I stopped working. I retired at twenty-two. Learned to get by on the money they'd given me. Learned to live with just my own company. Managed to make the days go by, just strolling around from one cafe to another, or going to the cinema, or sitting in the park. If I needed a woman it had to be a whore. I couldn't have friends or allow anybody to get too close. Didn't dare to have a drink even, because if my tongue got loose there was no knowing what I might come out with. Sometimes I went to the library and read books. Sometimes I went for long walks by the side of the canal. But I'll tell you something I never did. I never fed the pigeons in the park.

It just became my life after a while and I accepted it. That's what people do, you know. Adapt. Accept. Especially as we get older. Life becomes just consciousness, without any expectation of anything better. We live by habits. Time to move on every couple of months. Time to pack the big suitcase again.

What are you waiting for, I wonder? Why not get it over with? I'm tired. I've moved on enough times. It's a good night to die.

Would you like me to turn my back? Would that help? ... There. How's that?

I'm waiting.

I'm still waiting.

Where are you? God damn it! Mrs Rogers! Did a man go down the stairs?

For the love of Christ. Don't keep me waiting any longer.