I want to move on now to our last years at Hailsham. I'm talking about the period from when we were thirteen to when we left at sixteen. In my memory my life at Hailsham falls into two distinct chunks: this last era, and everything that came before. The earlier years - the ones I've just been telling you about - they tend to blur into each other as a kind of golden time, and when I think about them at all, even the not-so-great things, I can't help feeling a sort of glow. But those last years feel different. They weren't unhappy exactly - I've got plenty of memories I treasure from them - but they were more serious, and in some ways darker. Maybe I've exaggerated it in my mind, but I've got an impression of things changing rapidly around then, like day moving into night.

That talk with Tommy beside the pond: I think of it now as a kind of marker between the two eras. Not that anything significant started to happen immediately afterwards; but for me at least, that conversation was a turning point. I definitely started to look at everything differently. Where before I'd have backed away from awkward stuff, I began instead, more and more, to ask questions, if not out loud, at least within myself.

In particular, that conversation got me looking at Miss Lucy in a new light. I watched her carefully whenever I could, not just from curiosity, but because I now saw her as the most likely source of important clues. And that's how it was, over the next year or two, I came to notice various odd little things she said or did that my friends missed altogether.

There was the time, for example, maybe a few weeks after the talk by the pond, when Miss Lucy was taking us for English. We'd been looking at some poetry, but had somehow drifted onto talking about soldiers in World War Two being kept in prison camps. One of the boys asked if the fences around the camps had been electrified, and then someone else had said how strange it must have been, living in a place like that, where you could commit suicide any time you liked just by touching a fence. This might have been intended as a serious point, but the rest of us thought it pretty funny. We were all laughing and talking at once, and then Laura - typical of her - got up on her seat and did a hysterical impersonation of someone reaching out and getting electrocuted. For a moment things got riotous, with everyone shouting and mimicking touching electric fences.

I went on watching Miss Lucy through all this and I could see, just for a second, a ghostly expression come over her face as she watched the class in front of her. Then - I kept watching carefully - she pulled herself together, smiled and said: ‘It's just as well the fences at Hailsham aren't electrified. You get terrible accidents sometimes.’

She said this quite softly, and because people were still shouting, she was more or less drowned out. But I heard her clearly enough. ‘You get terrible accidents sometimes.’ What accidents? Where? But no one picked her up on it, and we went back to discussing our poem.

There were other little incidents like that, and before long I came to see Miss Lucy as being not quite like the other guardians. It's even possible I began to realise, right back then, the nature of her worries and frustrations. But that's probably going too far; chances are, at the time, I noticed all these things without knowing what on earth to make of them. And if these incidents now seem full of significance and all of a piece, it's probably because I'm looking at them in the light of what came later - particularly what happened that day at the pavilion while we were sheltering from the downpour.

We were fifteen by then, already into our last year at Hailsham. We'd been in the pavilion getting ready for a game of rounders. The boys were going through a phase of ‘enjoying’ rounders in order to flirt with us, so there were over thirty of us that afternoon. The downpour had started while we were changing, and we found ourselves gathering on the veranda - which was sheltered by the pavilion roof - while we waited for it to stop. But the rain kept going, and when the last of us had emerged, the veranda was pretty crowded, with everyone milling around restlessly. I remember Laura was demonstrating to me an especially disgusting way of blowing your nose for when you really wanted to put off a boy.

Miss Lucy was the only guardian present. She was leaning over the rail at the front, peering into the rain like she was trying to see right across the playing field. I was watching her as carefully as ever in those days, and even as I was laughing at Laura, I was stealing glances at Miss Lucy's back. I remember wondering if there wasn't something a bit odd about her posture, the way her head was bent down just a little too far so she looked like a crouching animal waiting to pounce. And the way she was leaning forward over the rail meant drops from the overhanging gutter were only just missing her - but she seemed to show no sign of caring. I remember actually convincing myself there was nothing unusual in all this - that she was simply anxious for the rain to stop - and turning my attention back to what Laura was saying. Then a few minutes later, when I'd forgotten all about Miss Lucy and was laughing my head off at something, I suddenly realised things had gone quiet around us, and that Miss Lucy was speaking.

She was standing at the same spot as before, but she'd turned to face us now, so her back was against the rail, and the rainy sky behind her.

‘No, no, I'm sorry, I'm going to have to interrupt you,’ she was saying, and I could see she was talking to two boys sitting on the benches immediately in front of her. Her voice wasn't exactly strange, but she was speaking very loudly, in the sort of voice she'd use to announce something to the lot of us, and that was why we'd all gone quiet. ‘No, Peter, I'm going to have to stop you. I can't listen to you any more and keep silent.’

Then she raised her gaze to include the rest of us and took a deep breath. ‘All right, you can hear this, it's for all of you. It's time someone spelt it out.’

We waited while she kept staring at us. Later, some people said they'd thought she was going to give us a big telling-off; others that she was about to announce a new rule on how we played rounders. But I knew before she said another word it would be something more.

‘Boys, you must forgive me for listening. But you were right behind me, so I couldn't help it. Peter, why don't you tell the others what you were saying to Gordon just now?’

Peter J. looked bewildered and I could see him getting ready his injured innocence face. But then Miss Lucy said again, this time much more gently:

‘Peter, go on. Please tell the others what you were just saying.’

Peter shrugged. ‘We were just talking about what it would feel like if we became actors. What sort of life it would be.’

‘Yes,’ Miss Lucy said, ‘and you were saying to Gordon you'd have to go to America to stand the best chance.’

Peter J. shrugged again and muttered quietly: ‘Yes, Miss Lucy.’

But Miss Lucy was now moving her gaze over the lot of us. ‘I know you don't mean any harm. But there's just too much talk like this. I hear it all the time, it's been allowed to go on, and it's not right.’ I could see more drops coming off the gutter and landing on her shoulder, but she didn't seem to notice. ‘If no one else will talk to you,’ she continued, ‘then I will. The problem, as I see it, is that you've been told and not told. You've been told, but none of you really understand, and I dare say, some people are quite happy to leave it that way. But I'm not. If you're going to have decent lives, then you've got to know and know properly. None of you will go to America, none of you will be film stars. And none of you will be working in supermarkets as I heard some of you planning the other day. Your lives are set out for you. You'll become adults, then before you're old, before you're even middle-aged, you'll start to donate your vital organs. That's what each of you was created to do. You're not like the actors you watch on your videos, you're not even like me. You were brought into this world for a purpose, and your futures, all of them, have been decided. So you're not to talk that way any more. You'll be leaving Hailsham before long, and it's not so far off, the day you'll be preparing for your first donations. You need to remember that. If you're to have decent lives, you have to know who you are and what lies ahead of you, every one of you.’

Then she went silent, but my impression was that she was continuing to say things inside her head, because for some time her gaze kept roving over us, going from face to face just as if she were still speaking to us. We were all pretty relieved when she turned to look out over the playing field again.

‘It's not so bad now,’ she said, even though the rain was as steady as ever. ‘Let's just go out there. Then maybe the sun will come out too.’

I think that was all she said. When I was discussing it with Ruth a few years ago at the centre in Dover, she claimed Miss Lucy had told us a lot more; that she'd explained how before donations we'd all spend some time first as carers, about the usual sequence of the donations, the recovery centres and so on - but I'm pretty sure she didn't. Okay, she probably intended to when she began talking. But my guess is once she'd set off, once she'd seen the puzzled, uncomfortable faces in front of her, she realised the impossibility of completing what she'd started.

It's hard to say clearly what sort of impact Miss Lucy's outburst at the pavilion made. Word got round fast enough, but the talk mostly focused on Miss Lucy herself rather than on what she'd been trying to tell us. Some students thought she'd lost her marbles for a moment; others that she'd been asked to say what she had by Miss Emily and the other guardians; there were even some who'd actually been there and who thought Miss Lucy had been telling us off for being too rowdy on the veranda. But as I say there was surprisingly little discussion about what she'd said. If it did come up, people tended to say: ‘Well so what? We already knew all that.’

But that had been Miss Lucy's point exactly. We'd been ‘told and not told’, as she'd put it. A few years ago, when Tommy and I were going over it all again, and I reminded him of Miss Lucy's ‘told and not told’ idea, he came up with a theory.

Tommy thought it possible the guardians had, throughout all our years at Hailsham, timed very carefully and deliberately everything they told us, so that we were always just too young to understand properly the latest piece of information. But of course we'd take it in at some level, so that before long all this stuff was there in our heads without us ever having examined it properly.

It's a bit too much like a conspiracy theory for me - I don't think our guardians were that crafty - but there's probably something in it. Certainly, it feels like I always knew about donations in some vague way, even as early as six or seven. And it's curious, when we were older and the guardians were giving us those talks, nothing came as a complete surprise. It was like we'd heard everything somewhere before.

One thing that occurs to me now is that when the guardians first started giving us proper lectures about sex, they tended to run them together with talk about the donations. At that age - again, I'm talking of around thirteen - we were all pretty worried and excited about sex, and naturally would have pushed the other stuff into the background. In other words, it's possible the guardians managed to smuggle into our heads a lot of the basic facts about our futures.

Now to be fair, it was probably natural to run these two subjects together. If, say, they were telling us how we'd have to be very careful to avoid diseases when we had sex, it would have been odd not to mention how much more important this was for us than for normal people outside. And that, of course, would bring us onto the donations.

Then there was the whole business about our not being able to have babies. Miss Emily used to give a lot of the sex lectures herself, and I remember once, she brought in a life-size skeleton from the biology class to demonstrate how it was done. We watched in complete astonishment as she put the skeleton through various contortions, thrusting her pointer around without the slightest self-consciousness. She was going through all the nuts and bolts of how you did it, what went in where, the different variations, like this was still Geography. Then suddenly, with the skeleton in an obscene heap on the desktop, she turned away and began telling us how we had to be careful who we had sex with. Not just because of the diseases, but because, she said, ‘sex affects emotions in ways you'd never expect’. We had to be extremely careful about having sex in the outside world, especially with people who weren't students, because out there sex meant all sorts of things. Out there people were even fighting and killing each other over who had sex with whom. And the reason it meant so much - so much more than, say, dancing or table-tennis - was because the people out there were different from us students: they could have babies from sex. That was why it was so important to them, this question of who did it with whom. And even though, as we knew, it was completely impossible for any of us to have babies, out there, we had to behave like them. We had to respect the rules and treat sex as something pretty special.

Miss Emily's lecture that day was typical of what I'm talking about. We'd be focusing on sex, and then the other stuff would creep in. I suppose that was all part of how we came to be ‘told and not told’.

I think in the end we must have absorbed quite a lot of information, because I remember, around that age, a marked change in the way we approached the whole territory surrounding the donations. Until then, as I've said, we'd done everything to avoid the subject; we'd backed off at the first sign we were entering that ground, and there'd been severe punishment for any idiot - like Marge that time - who got careless. But from when we were thirteen, like I say, things started to change. We still didn't discuss the donations and all that went with them; we still found the whole area awkward enough. But it became something we made jokes about, in much the way we joked about sex. Looking back now, I'd say the rule about not discussing the donations openly was still there, as strong as ever. But now it was okay, almost required, every now and then, to make some jokey allusion to these things that lay in front of us.

A good example is what happened the time Tommy got the gash on his elbow. It must have been just before my talk with him by the pond; a time, I suppose, when Tommy was still coming out of that phase of being teased and taunted.

It wasn't such a bad gash, and though he was sent to Crow Face to have it seen to, he was back almost straight away with a square of dressing plastered to his elbow. No one thought much about it until a couple of days later, when Tommy took off the dressing to reveal something at just that stage between sealing and still being an open wound. You could see bits of skin starting to bond, and soft red bits peeping up from underneath. We were in the middle of lunch, so everyone crowded round to go ‘urgh!’. Then Christopher H., from the year above, said with a dead straight face: ‘Pity it's on that bit of the elbow. Just about anywhere else, it wouldn't matter.’

Tommy looked worried - Christopher being someone he looked up to in those days - and asked what he meant. Christopher went on eating, then said nonchalantly:

‘Don't you know? If it's right on the elbow like that, it can unzip. All you have to do is bend your arm quickly. Not just that actual bit, the whole elbow, it can all unzip like a bag opening up. Thought you'd know that.’

I could hear Tommy complaining that Crow Face hadn't warned him of anything of that sort, but Christopher shrugged and said: ‘She thought you knew, of course. Everyone knows.’

A number of people nearby murmured agreement. ‘You've got to keep your arm dead straight,’ someone else said. ‘Bending it at all's really dangerous.’

The next day I could see Tommy going about with his arm held out very rigidly and looking worried. Everybody was laughing at him, and I was cross about that, but I had to admit, there was a funny side to it. Then towards the end of the afternoon as we were leaving the Art Room, he came up to me in the corridor and said: ‘Kath, can I just have a quick word?’

This was maybe a couple of weeks after the time I'd gone up to him in the playing field to remind him about his polo shirt, so it had got about we were special friends of some sort. All the same, his coming up like that asking for a private talk was pretty embarrassing and threw me off balance. Maybe that partly explains why I wasn't more helpful than I was.

‘I'm not too worried or anything,’ he began, once he'd got me aside. ‘But I wanted to play safe, that's all. We should never take chances with our health. I need someone to help, Kath.’ He was, he explained, concerned about what he'd do in his sleep. He might easily bend his elbow in the night. ‘I have these dreams all the time where I'm fighting loads of Roman soldiers.’

When I quizzed him a bit, it became obvious all kinds of people - people who hadn't been there that lunch-time - had been coming up to him to repeat Christopher H.'s warning. In fact, it seemed a few had carried the joke further: Tommy had been told of a student who'd gone to sleep with a cut on the elbow just like his and woken up to find his whole upper arm and hand skeletally exposed, the skin flopping about next to him ‘like one of those long gloves in My Fair Lady’.

What Tommy was asking me now was to help tie a splint on the arm to keep it rigid through the night.

‘I don't trust any of the others,’ he said, holding up a thick ruler he wanted to use. ‘They might deliberately do it so it comes undone in the night.’

He was looking at me in complete innocence and I didn't know what to say. A part of me wanted badly to tell him what was going on, and I suppose I knew that to do anything else would be to betray the trust we'd built up since the moment I'd reminded him about his polo shirt. And for me to strap up his arm in a splint would have meant my becoming one of the main perpetrators of the joke. I still feel ashamed I didn't tell him then. But you've got to remember I was still young, and that I only had a few seconds to decide. And when someone's asking you to do something in such a pleading way, everything goes against saying no.

I suppose the main thing was that I didn't want to upset him. Because I could see, for all his anxiety about his elbow, Tommy was touched by all the concern he believed had been shown him. Of course, I knew he'd find out the truth sooner or later, but at that moment I just couldn't tell him. The best I could do was to ask:

‘Did Crow Face tell you you had to do this?’

‘No. But imagine how angry she'd be if my elbow slipped out.’

I still feel bad about it, but I promised to strap his arm for him - in Room 14 half an hour before the night bell - and watched him go off grateful and reassured.

As it happened, I didn't have to go through with it because Tommy found out first. It was around eight in the evening, I was coming down the main staircase, and heard a burst of laughter rising up the stairwell from the ground floor. My heart sank because I knew immediately it was to do with Tommy. I paused on the first-floor landing and looked over the rail just as Tommy came out of the billiards room with thunderous footsteps. I remember thinking: ‘At least he's not shouting.’ And he didn't, the whole time he went to the cloakroom, got his things and left the main house. And all that time, laughter kept coming from the open doorway of the billiards room, and voices yelling things like: ‘If you lose your temper, your elbow will definitely pop out!’

I thought about following him out into the evening and catching up with him before he got to his dorm hut, but then I remembered how I'd promised to put his arm in a splint for the night, and didn't move. I just kept saying to myself: ‘At least he didn't have a tantrum. At least he kept hold of that temper.’

But I've gone off a bit. The reason I was talking about all this was because the idea of things ‘unzipping’ carried over from Tommy's elbow to become a running joke among us about the donations. The idea was that when the time came, you'd be able just to unzip a bit of yourself, a kidney or something would slide out, and you'd hand it over. It wasn't something we found so funny in itself; it was more a way of putting each other off our food. You unzipped your liver, say, and dumped it on someone's plate, that sort of thing. I remember once Gary B., who had this unbelievable appetite, coming back with a third helping of pudding, and virtually the whole table ‘unzipping’ bits of themselves and piling it all over Gary's bowl, while he went on determinedly stuffing himself.

Tommy never liked it much when the unzipping stuff came up again, but by then the days of his being teased were past and no one connected the joke with him any more. It was just done to get a laugh, to put someone off their dinner - and, I suppose, as some way of acknowledging what was in front of us. And this was my original point. By that time in our lives, we no longer shrank from the subject of donations as we'd have done a year or two earlier; but neither did we think about it very seriously, or discuss it. All that business about ‘unzipping’, that was typical of the way the whole subject impinged on us when we were thirteen.

So I'd say Miss Lucy had it about right when she said, a couple of years later, that we'd been ‘told and not told’. And what's more, now I think about it, I'd say what Miss Lucy said to us that afternoon led to a real shift in our attitudes. It was after that day, jokes about donations faded away, and we started to think properly about things. If anything, the donations went back to being a subject to be avoided, but not in the way it had been when we were younger. This time round it wasn't awkward or embarrassing any more; just sombre and serious.

‘It's funny,’ Tommy said to me when we were remembering it all again a few years ago. ‘None of us stopped to think about how she felt, Miss Lucy herself. We never worried if she'd got into trouble, saying what she did to us. We were so selfish back then.’

‘But you can't blame us,’ I said. ‘We'd been taught to think about each other, but never about the guardians. The idea the guardians had differences between them, that never occurred to us.’

‘But we were old enough,’ Tommy said. ‘By that age, it should have occurred to us. But it didn't. We didn't think about poor Miss Lucy at all. Not even after that time, you know, when you saw her.’

I knew straight away what he meant. He was talking about the morning early in our last summer at Hailsham, when I'd stumbled across her up in Room 22. Thinking about it now, I'd say Tommy had a point. After that moment it should have been clear, even to us, how troubled Miss Lucy had become. But as he said, we never considered anything from her viewpoint, and it never occurred to us to say or do anything to support her.