The next evening, I reached a crisis of sorts. I'd been harbouring a vague belief that if all the Muggle-born attacks resulted in a premature end to the term (as rumour now suggested was entirely likely), and students going home early, then this would constitute some sort of academic general amnesty. Consequently, my accumulated undone homework now included no fewer than six essays: three for Potions (Professor Slughorn had been easily cajoled into extending the due dates for the first two) and one each for Transfiguration, Charms, and Defence Against the Dark Arts. Moreover, I still hadn't even started O.W.L. revision, and by now that made me unusual. Most of the other fifth-year Slytherins were spending at least some of their free periods in the common room, sitting amid disorderly piles of parchment, staring glumly at their own handwritten notes or making more of them.

It was the first time I'd been so far behind with work, and the only solution that suggested itself was the same one I've been using, more or less, ever since. I would just have to settle in after dinner at the largest common-room table, make a start on Slughorn's first essay, and keep writing until it and all the rest of the backlog had been satisfactorily dealt with. I could stay up all night if necessary (and it probably would be). Mr. Danforth Diggle, proprietor and editor of the Magical Monthly (now defunct, alas), was wont in later years to accuse me of being his most slothful employee, and I daresay he had a point. But even he never questioned my capacity for sustained, unremitting effort, provided I was given no real choice in the matter.

My progress was slow at first. A small knot of second-year boys had somehow obtained a box of fake Instant Darkness Powder, and were amusing themselves by throwing pinches of it into the fireplace. Actinic flashes alternated with brief total blackouts; it was difficult to see the words in front of me, and the high-pitched merriment made it impossible to concentrate on them. The vigorous objections of a grey-haired old wizard whose portrait hung over the mantelpiece didn't help, either -- he was succeeding only in teaching the boys some new swear words. But, just as the nearest prefect was starting to look annoyed enough to tell them to leave off, the little miscreants ran out of powder and disappeared down the stairs to their dormitory. After that, things quietened down considerably. It was mostly the O.W.L. and N.E.W.T. students who were still up and we didn't disturb each other much, beyond the odd whispered enquiry after the allotropes of adamant, or what one should do with armadillo bile.

At around ten o'clock I finished the first essay (“Controlling Concentration in Swelling Solutions�), sat up, and looked around. There were a few of us left: Edwin Rosier and Tom Riddle at my table, a couple of seventh-years sharing a couch by the door, and Athena working with Walburga Black on something behind me. The grey-haired wizard, having recovered his dignity by now, appeared to be falling asleep, although I suspected that his doze was mostly pretence. I caught the eye of Barabbas Lestrange, at a table by himself in a corner of the room; his quill was not in his hand, and he didn't seem to be working on anything. He was simply sitting as one sits on a train, waiting. Occasionally he glanced at Tom, but Tom never looked in his direction.

I really needed to write something on “Cross-Species Transfiguration and the Lunar Phase� to hand in to Dumbledore, but I couldn't face that just yet. Instead I threw myself into another Potions assignment, and found the words starting to come easily at last. This was what I needed: I could write handily enough about anything under the sun (if I do say so myself), provided I didn't have to do it under the sun, with all the distractions of Hogwarts in the daytime. Slughorn would be pleased: he had asked only for two rolls of parchment, but I would be giving him nearly three. I wrote on, until the greenish illumination of the common-room lights faded to an even feebler glimmer than usual, as if to match the darkness of the lake above. They did that every night, but I was seldom awake to see it. The wizard in the portrait had begun to snore softly, and I was dimly aware of others packing up their things and leaving; I didn't stop to watch them go. The next time I looked up, it was well after eleven, and the room was empty except for Tom and me.

He had turned his wand into an improvised desk-lamp, propping it up on a stack of textbooks; I don't remember hearing him say Lumos, but perhaps he was already doing that one non-verbally. He was reading a thick old tome with crinkled pages, staring intently at a long list of what appeared to be surnames. I don't know where that book came from, but the people in it weren't British.

Tom sensed me watching him, and looked up with an annoyed expression. He glanced around the room, confirming that we were alone, before turning his attention to me.

“You'll strain your eyes, doing homework this late. Nearly finished, I hope?�

“Nowhere near,� I replied with a sigh. “I'll be hours yet: essays to do for Slughorn, and Merrythought, and Dumbledore.�

For a moment I thought he was going to order me down to the girls' dormitory, but he could hardly do that, prefect though he was, while he sat up in the common room himself.

“Are you turning in soon?� I ventured.

“No point. Rosier is still awake in there, or else snoring like a steam engine.�

I shrugged, lit my own wand, and turned back to my essay. I never enjoyed idle conversation with Tom Riddle; I suppose I could claim, now, that I sensed his wickedness, but it wasn't really anything so definite. He just seemed cold and brusque, unless you were giving him information he wanted, or he was asking you to do something for him; then he was all attention, and made you feel important just for listening to him.

A few minutes later Tom pushed his chair back; in the silence, its legs seemed to screech on the flagstone floor. Without saying a word, he got up, moved to another table, and sat down there. Not wanting to show that I was watching him, I let my hair fall in front of my face -- I wore it long in those days -- as I bent over my parchment. What was he up to? The book he'd been reading was still open at my table; now he was writing something, in that Muggle diary of his. He was intensely focused on whatever it was, scribbling furiously, his hand twitching back and forth across one line after another. In the green gloom, and at this distance, I couldn't hope to read what he was committing to the diary's pages, but it mattered to him deeply, that much was evident. His face was screwed up in a way that suggested pain, desperation even, as though he needed to get the words out before they poisoned him. I half-expected to hear him groan, but the only sound in the dungeon was the harsh scratching of his quill, and my own shallow breathing.

Progress on my essay slowed to a crawl; whatever Tom was doing was far more interesting. In the time it took me to get down three more sentences, he must have written enough to fill a dozen pages -- although oddly enough, I'm sure I never saw him turn a page the whole time. What on earth had he been up to? I never would have guessed, before that night, that a model student like Riddle might be involved in anything that he had to write about like a boy possessed. Which just shows how wrong you can be about people -- if I learned anything from knowing Tom, it was not to trust a pleasant face.

I don't know how long we sat like that, in near-darkness, Tom writing and I pretending to write. He never paused to think or compose; he took his quill off the page only to dip it in fresh ink, and even that was the briefest possible interruption: a quick, occasional spasm that was over in an eyeblink. I watched him through my fringe in fascination, intensely curious, wishing I could think of some way to get a look at that diary without Tom knowing I'd looked. I wondered whether some close friend of his might be persuaded into reading it, and then divulging the contents. But -- it occurred to me for the first time that night -- popular as Tom was, there was no-one he'd be likely to share his personal diary with. No-one was that close to him, even then.

I was just starting to give myself a good talking-to (never mind Riddle, my girl, you've still got masses of homework to get through, and Dumbledore for one doesn't take weak excuses) when I was distracted again by a snatch of faint, sharp music from the direction of the corridor outside, which I recognised at once as Zinn's flute. The sound seemed to be coming from some distance away, and it came and went, as though the Piper were sometimes there and sometimes not.

It was a new sound to Tom. He abruptly stopped writing, resting his quill-hand on the table, his head held up and his mouth slightly open as he listened. After a few bars he saw that I was listening, too.

“Avery, what's that?� he snapped.

“Zinn,� I told him. “He played the same tune yesterday by the lake, or one very similar. Well,� -- the music almost seemed to have heard me, and at once darted aside onto a completely different melodic path as if to confound me -- “somewhat similar.�

The effect on Tom was remarkable. In an instant his concentration was gone, his focus elsewhere. Whatever had been so important to him a moment ago was less urgent than listening to Zinn's piping. He began to shift agitatedly in his chair. Presently the music grew louder, then faded, as if Zinn had passed our common-room door and wandered away again down the passage; Tom waited with obvious anxiety for its return. He had dropped his quill and now held his wand, gripping it tightly. As he fidgeted, the light from its tip made grotesque, deformed shadows that stalked around the walls, ambushing the Slytherin banners that hung there.

I forced a nervous laugh. “He must be patrolling the dungeons. Well, Dippet did say 'Hogwarts from top to bottom'. Although, if we had any monsters down here, I think we'd already know about them. Wouldn't we, Tom?� That last addition, I have to admit, was more for my benefit than his.

Abruptly, Tom was on his feet. “Stay here,� he commanded, before dashing out of the room, leaving the door swinging open in his haste.

“Tom, it's after hours!� I called after him. “You're a prefect, you can't gad about the castle at this hour of the morning!�

But he was gone. Idiot, was my first thought. Watching the Piper at work, trying to whistle up monsters, wasn't all that fascinating, certainly not worth getting into trouble for. Tom would have been in trouble, too, if he'd run into any of the ghosts. (Except the Bloody Baron, of course; he looked after his own.)

My second thought was, He's left the diary behind. There it lay, open at the page Tom had been writing on a few minutes before. The room's glaucous light was feebler than ever now, but my own wand would be ample illumination to read by, if I dared.

Well, what would you have done? Left it there, probably, and minded your own business. But you must remember that as I sat there that night, fifteen years old with my school books piled in front of me, I had heard the name “Lord Voldemort� only once or twice, and then only as a kind of joke, a nickname that some of Tom's friends used. I didn't see a reason to leave any of Riddle's secrets uninvestigated if I could help it; I was over at his table inside a minute. I picked up the chair he'd knocked over as he'd hurried off, and sat myself in front of that slim pocket-sized volume. It was open at the second week of June; I flicked quickly through some of the pages, but there didn't seem to be anything written on them. That didn't put me off in the slightest. If Tom was using invisible writing, he clearly didn't want anyone to read what he recorded in his diary, and that made me all the keener to see whatever it was.

“Aparecium!� I tried.

“Effundo!�

“Revelio!�

I've always had a knack for Revealing Charms. For a few moments I had that sensation in the pit of my stomach that meant the charm had worked, that something was going to show itself, and then:

Who the devil are you?

The words appeared, blood-red ink scrawled across the ruled pages, but more than that: they were in my head, too, as if the diary were annoyed that I had poked at it.

Dippet, you meddling fool! Four years to get in, and now it might as well be enchanted shut again, for all the good it's doing me. I can't hang around in there all the time... That blithering Gyppo needs to be dealt with!

Ah, I know you now. Avery, isn't it? From the weakling side of the family, alas. Cousin Bernard's far more useful than you'll ever be, even though he couldn't Charm his way out of an overcoat. At least he makes the effort -- I wouldn't trust you to give me the correct time of day, you'd get bored halfway through and give up, wouldn't you?

Pain, all over my body, and yet it was a strangely dull agony, as if I were only dreaming of being tortured, and could, if I chose, go on reading despite it. Does that hurt?, enquired the diary mildly, stabbing the words into my brain. Good. Only the living feel pain. I'll teach Mrs. Cole that, if she crosses me one more time, the stupid old frump...

Think no-one missed that copy of Unfogging The Future, do you, Avery? Well, you're wrong. Don't try to deceive Lord Voldemort: he knows, he always knows!

Slytherin's own servant, now mine! Yes, you'd better keep an eye on me, Dumbledore; do you know that I'm watching you, too?

I felt Tom's thoughts battering at me, the intensity of the emotions he'd put into this Dark artefact I was holding. But I couldn't stop reading it. Or wouldn't stop, I don't know which.

Your mother was a Mudblood, wasn't she? And you call yourself a Slytherin, and pretend you're as worthy as the rest of us!

No, I'm not Olive Hornby, whoever she is. Get out of the way, you witless girl!

Half the time the words were illegible, and I seemed to hear only an eldritch hissing, as if Tom had chosen to whisper his words in some sibilant foreign tongue. But it was the references to myself that were most unnerving: a book shouldn't know when it's being read, but there was something in this one that knew, and knew more about me than Tom ought to have known. For my mother really was Muggle-born, though I was careful never to mention that at school if I didn't have to, especially not to anyone in Slytherin. And I really did once walk out of Flourish and Blotts with a Divination book I'd forgotten to pay for, and never went back to make restitution.

A shadow moved on the far wall. The diary had me so enthralled that I didn't react for a second, and then it was too late.

“Expelliarmus!� My wand flew across the room, into Tom's waiting left hand. He stood in the doorway for a moment, a wand in each hand, the expression on his face a startling mixture of anger, dawning realisation, and a savage excitement.

“You shouldn't be reading that,� he snapped.

“Tom, I'm really, really sorry.� I did my best to look distressed and remorseful. “You're right, I shouldn't have --�

“Lumos!� The light from my wand, which had failed when it was taken from me, returned. Tom smiled with delight. “Ah, this one obeys me.� He held his prize between two fingers, admiring it. “Ash and -- what is it?�

“Unicorn hair. Tom, I do apologize for looking at your book, that was very wrong of me, but -- could I have my wand back, please?�

“No,� he stated flatly. “As it happens, I have a use for it.� He paused expectantly, watching me.

There was a long silence. I didn't know what to say, and began to feel rather wretched and confused about it all. As the moments dragged on, Tom's features relaxed by degrees, as if he were gradually regaining control. “Good,� he said eventually. “You didn't pry too far into my little book, then. It's not polite to spy on other people's thoughts, you know. No, don't apologize, I've already heard it. You're going to make it up to me instead. I was just looking for a wand to borrow, and now here's this one, ready and apt to my hand. You won't miss it; I'll return it in the morning.�

“But -- what do you want it for?�

“Never you mind. Isn't it about time you went to bed?�

I could have saved myself an awful lot of trouble by meekly saying “yes� and escaping downstairs. Instead, nosiness (what was that diary?) and a strong sense of pique pushed me to utter the impetuous words: “I want to come.�

“What?�

“Whatever you're going to do with my wand, I want to see you do it.�

His mouth quirked upwards at the corners; he considered for a long moment. He was going to refuse me, I knew, and perhaps that wouldn't be such a bad thing...

“All right,� he replied at last, carelessly. “I expect we'll both learn something useful from the experience. Useful to me, that is.� He gestured with my wand towards the door. “You go first.�

I had no shoes on, and I briefly considered asking Tom to wait while I ran down to the girls' dormitory to get some. But what if he grew impatient, I worried, and left without me? What would happen to my wand? I scurried out into the corridor, quickly, before either of us could change our minds.

As his steps echoed behind me down the pitch-dark dungeon passage -- unlit at this time of night, except by the two wands Tom was holding -- I was soon regretting the rash decisions that had brought me to this point. Why couldn't I have left that slim Muggle volume well alone? What had I expected to find in it, anyway? Too late, it was done; curiosity had landed the cat in the soup (again), and now I would have to lie in it. I tried to think of something else I could do for Tom to make it up to him, but nothing -- nothing decent, anyway -- came to mind. Besides, Tom wasn't the sort of person who took suggestions. He had the ideas, and his friends, if they wanted to remain his friends, went along with them.

Of course, even in the dark, I knew exactly where we were. All of us in Slytherin had long since thoroughly explored the dungeons of Hogwarts, which we regarded as the private fiefdom of our House. One never knew when it might be useful to absent oneself down there for a while, and if nothing else, there was innocent fun to be had by misdirecting the odd disoriented Hufflepuff. So I was surprised when Tom stopped at a small door, which I'd always taken to be a storage cupboard of some kind. It was a door that was always locked, and no-one I knew had ever managed to open it, even by magic.

“That one's hopeless,� I began to tell Tom. “It's--�

But he just laid a finger across his smiling lips, softly bidding me hush, as he fished an ancient-looking iron key out of an inside pocket in his school robes. I had to suppress a strong desire to ask him how and where he got that key (and could I have one?), recalling that he didn't exactly owe me any favours just then.

A breath of cold, dank air flowed past us when the door was opened. The space behind was indeed no larger than a cupboard, but it contained a tiny staircase, designed perhaps for the feet of goblins or house-elves. Tom gestured to indicate that I should descend first, and I went ahead of him, my stockings padding on the hard stone. I couldn't quite see where I was putting my feet, but at least the steps were all worn clean and smooth. How they got that way, I've no idea; we were well below the level of any classrooms I was ever in.

When we emerged, we must have been in a long straight passage, because there was utter blackness ahead, with nothing to reflect our meagre light back to us. Tom strode confidently into the dark, and I did my best to keep up with him. To either side I could see that the stone walls were covered with something like moss, glistening in the dim illumination, and occasionally there would be a ghostly pillar shaped into a silently screaming gargoyle. I don't mind admitting that by now I was starting to feel a little bit apprehensive, and had to comfort myself with the thought that Tom was a responsible prefect. Whatever he was planning wouldn't be too awful, surely? Just as well that I had no true understanding then of what Tom was, or I should have been terrified out of my wits.

We stopped at a hefty-looking door, with a tiny barred window in it at eye level. Only then did I realise that we had come to the real dungeons of Hogwarts Castle. Not the classroom-dungeons, that you've all studied and learned and misbehaved in, but the cells for holding prisoners. I'd never really believed Mr. Pringle -- he was the caretaker in those days -- on the occasions when he cornered us where we shouldn't have been, and began to mutter nastily about thumbscrews, and losing students for a few months “down below�. He never did any such thing, I'm sure. But he might have picked up that evil little performance from his predecessor in the job, who in turn probably got it from his -- and, well, I'm inclined now to think it had some basis in fact, if you go back far enough. One thing's for certain, anyway: if you and I had gone to school in an age when delinquent students did their detentions in those cells, we should all have been a lot politer and better behaved. The very sight of that door, shut solid with rust and filthy fist-sized bolts, had me vowing never to talk in class again.

“Alohomora!� Hinges screeching, the door swung open at Tom's command, and he ducked beneath the low lintel to enter. I didn't really want to follow him in there, but there was no way I was going to stand in the inky blackness on my own.