This is Kelly, 3.00 a.m.

When I invited Kelly back to my room that night it wasn't for sex, it wasn't as clear-cut as that. I liked her, no doubt about it, but I couldn't tell if we were destined to be friends or lovers. I don't just mean that I wasn't sure how she viewed me, I wasn't sure how I viewed her either. We were in a grey area, as if we'd wandered into the disputed border territory between friendship and romance, all we could do was lie low and wait and see which side won out, which side of the border we'd end up on.

It was around midnight, I don't know the exact time, we'd been to the pub in town and walked back. She lived in the halls opposite mine, but I invited her up for coffee. She laughed when I said this, but I really did mean just coffee. That's the way I use words, anyway life is confusing enough without ambiguous application of language.

Besides which, I love late night conversations. Not drunken, party-late gang or group conversations, which always pitch to the lowest conversational denominator, but one-on-one, after-midnight conversations where the usual conversational limits no longer apply, instead the careless mix of silliness and philosophical exchange where everything is, if not possible, then both ponderable and mockable. This is where friendships are forged, with conversations that bond you together. Conversations - even the word is good, it conjures up so much - converse - sensation - satiation - verse -versatility - sat (well you're invariably sat down).

I only had one chair, the one tucked under my desk, so we sat side by side on my bed. Not flirtatiously close, but not so far away either. We were, I suppose, sitting in the disputed border territory between friendship and romance. Over the course of the next few hours, I guessed, we'd have moved an inch or so either way, and we'd know.

I filled up the kettle with water from my basin, plugged it in and switched it on. You see, coffee was on its way, I didn't rip my clothes off and plunge on top of her the minute we'd walked through the door. That would be unfair, forcing my own meaning into the words 'come back for coffee'. Not just rape of Kelly, but rape of the English language too.

We talked while we were waiting for the kettle to boil, and talked more after I'd poured the water into two mugs, stirred in coffee and milk. No sugar, just as well, as I didn't have any. We sat on the bed and talked about the world. About why elephants are my favourite animal. And Kelly's favourite animal too. About that man we'd met in the pub who thought he could make music with his nose, but just made an unpleasant snotty rasp. And about the books on my mantle. And about the word mantle, the least macho word in the English language beginning with 'man'.

I made more coffee. Time passed. The clock by my bed showed 1.38. By the time I'd made the coffee it was 1.39. By the time I'd sat down it was 1.40.

Kelly spoke. She said: "When I seven years old I caught a frog."

"Did you?" I said. I didn't realise at the time how significant Kelly's statement was, that she was about to reveal her innermost secret, the core of her being. I just said: "Well done."

"Very well done actually. The words 'I caught a frog' don't begin to convey how hard it was. It was during the summer holidays, you know, when you're seven those holidays last forever."

"Until they end."

"Last forever until they end, like all good things." (She laughed at her own words). "We had a little pond in our back garden, I used to love that pond, lying dead still beside it and watching every movement, seeing a fly land on the water, the eyes of a fish catching sight of it and the fish swimming up and munching it in one great gulp. Watching the sun reflecting in the water, looking more like the sun than it does in the sky - it's too bright in the sky.

"One day, near the start of the holidays, I saw a frog sitting on a lily pad. A classic frog pose."

"Almost clichéd."

"Perhaps, but I was seven, too young to spot a frog cliché when I saw one. Innocent, even, of the fact that frog clichés existed. All I recognised was a frog and I decided to catch it. I extended my hands towards it, slowly, nervously, but while I was still inches away I felt it leap over my hands and splashed into the depths of the pond.

"It became my goal, that summer, to catch the frog. Well I didn't have many friends at the time, I'd just changed school and there weren't any children in my street I could play with. I had to make my own fun."

"A frog's as good a friend as any."

"Exactly. I wanted to make friends with the frog. But before I could be friends with it I had to catch it. And that was tricky.

"The frog always sat on the same lily pad. A creature of habit, so I had plenty of chances, but it always saw me, no matter how careful I was, no matter how slowly I advanced my hands, it always hopped away before I could grab it.

"I was getting better though. As the summer progressed my hands were getting closer, almost touching it before it sprang away.

"The last day of the holiday eventually arrived and I was determined to catch it, I would never have another chance (I don't know how I knew that but I did). I dedicated the whole day to it. I got up early, crept out of the back door and crawled slowly towards the pond, not wanting to give the frog any opportunity of seeing me coming. Luckily it had its back to me and didn't notice my crawling down the garden path.

"Within an hour I was by the side of the pool. The frog hadn't moved in all that time. How it managed to eat I don't know, it never seemed to do anything other than sit on that lily pad.

"I waited for another hour, not moving, making sure that the frog was used to my being there, accepted me as part of the general being of things. Then I started to move my hands towards it. Oh-so-slowly. Slower than a snail, so slowly that if the frog had turned and looked at me the only thing it could have seen moving was time itself."

"At last my hands were there, around the frog, and I made a grab. I expected to hear the splash of frog escaping, but there was none. Then I felt it in my hands, wet and squishy, cold but also alive.

"Hello Frog," I whispered. I held it there for what seemed like forever, but almost certainly wasn't. Feeling its heart beating within my cupped hands. Then, eventually, it was time to let the frog go.

"I opened my hands, slowly, so that I could get a good look at him before he leapt away. "Hello frog," I said again, as our eyes met. I took my top hand away, and waited for the splash.

"But the frog just sat there. Sat on my hand, looking at me. "Hello frog," I said again, in a whisper this time. I could feel the frog looking at me, trying to communicate, his look conveyed so much, so much more than mere words. The frog was speaking to me."

"What did it say?"

"I don't know. I don't speak frog.

"We sat like that for a long time, sharing, I don't know what. What can a frog share with a girl of seven, we lived completely different lives, breathed differently, ate differently, inhabited distinct social circles. And yet … there was something. We shared something. Just for those few minutes, but we were so close. Until, eventually, it was time for the frog to go, and I felt the power of its legs pressing into my hand, then ping, off it flew."

Suddenly Kelly started crying. She sobbed uncontrollably for several minutes. I put my arms around her and tried to console her, but she was lost to me, in a world of her own. I'd have had more chance of conversing with frogs at that moment than I had of connecting with Kelly.

Eventually the sobbing slowed and she slowly returned to the world, blinking slightly, as if startled to be there.

I didn't know what to say, it wasn't as if there was a reason for her tears, not that I could see, so I said nothing, waiting for her to explain. There was silence for a while, just the sound of us breathing. I removed my arm from her shoulder, to have left it there would have been forward, would have forced her to make a decision. And this wasn't the time.

Eventually she spoke, a whisper, as if she no longer had any strength with which to project her voice.

"What I'm about to tell you," she said, "is something I've never told anyone else before. Never, not boyfriends, not girlfriends, not my parents. Especially not my parents."

"I can keep a secret," I said, helplessly.

"It's about the frog."

"The frog when you were seven?"

She tried to speak, but in the end just nodded. Yes, that frog.

"I forgot all about the frog. As you do, I grew up, made friends, played games, did stuff, then I grew up some more and got into boys and did other stuff. All memory of there having been a frog in my garden when I was seven was gone, there was just too much stuff in the world."

"Just one grain of sand in a beach of memories."

"Exactly. Well, nearly exactly, one nerve-cell of memory in a beach of memory-cells."

"I can only apologise for the ineptitude of my metaphor." She smiled at this, her first smile for a while.

"There was one boy I became particularly fond of, he became my first proper boyfriend. Not my first kiss, not my first grope, but my first penetrative sex. Simon his name was, he was a couple of years older than me, I thought he was so grown up. He was ever so clever too, something of a child genius. He passed his A levels at 15 and went to university later that year. By the time I was doing my A levels he'd started his PhD, and he had money by then too - sponsored by a major company who'd spotted his potential, he had a car and a wad of ready.

"You were still going out then?"

"Still going out. Usually I only saw him during school holidays, as I wasn't trusted to go and visit him. Until I turned 17, I was allowed to go and stay with him for my 17th birthday."

"And where was this?"

"Oh Cambridge, he'd had his pick of universities but wanted the best. Apparently Oxford was as good academically but rubbish at sports."

"Sporty as well as clever?"

"Oh, perfect at everything was Simon. Good looking too. Could have done anything he wanted, been anything he wanted. In fact he probably did."

"You don't mind if I hate him do you?"

"Be my guest. You'll really hate him soon. When you find out what he did."

"Is this before or after the penetrative sex?"

"Oh after. Anyway, he chose to study psychology. He thought it was the sloppy backward child of the social sciences, the field of science where there was most potential for new discovery. That's what he wanted to do, to make a major breakthrough. And I was to be his first big experiment."

"Why, were you a psychological challenge?"

"Not then, no, I was pretty well balanced for a teenager. Simon's field of study was memory. He was fascinated about how memory worked, how some major events in our lives could be lost, yet minor incidents not just remembered, but seemingly ever-prominent.

"He'd learnt that memory was stored in cells in the brain, but wanted to know how these stored memories were triggered. He'd done the usual tests, words, images, sounds, lighting, moods, hypnotism. But this was repeating what other psychologists had done before him, he wanted to do something new, something that hadn't been tried."

"Electricity was the answer. Oh sure, scientists had been zapping brains with electric currents for decades, asylums and graveyards were full of their victims, but he was much more precise, he was after a tiny charge, directed so that it would excite just a single cell, a single cell that would contain a single memory. He'd designed his own machine, so exact it could be used to warm a single grain of sugar in a bowl, leaving the rest of the bowl at room temperature."

"Handy."

"Not of any practical day-to-day use, but exactly what he needed for the experiment.

"I guess he must have loved me in a unique way, as he wanted me to be his first experiment. Maybe he hoped he'd hit a memory about him.

"It was all done in secret of course, he'd never have got permission. It's the sort of idea that gives Ethics Committees nightmares. So we went to his lab late one night, when everyone else had gone home, or to the student bar. He had his own key, he was often the last there.

"He sat me down in a chair and plugged me in to his contraption. It was all very 70's sci fi."

"Did he cackle madly as he strapped you in?"

"No, but he did have a worrying smile. I should have stopped him there and then, but I really did love him. Trusted him. You know what it's like when you're 17."

"Absolutely, almost half of all 17 year olds get done away by mad-scientist boyfriends. It's the biggest killer."

"Well it didn't kill me, but it did …"

And again Kelly burst into tears, more controlled this time, not quite taking her away. She stopped crying after about five minutes and continued her story.

"I felt the shock as it hit me. A warm fuzzy sensation in the head, then … And then it was the frog."

"The frog?"

"The memory cell he'd hit was the one with the frog in it. He'd been right in that sense, the current was so fine it'd hit one single cell of memory. But he'd got the charge wrong, hopelessly wrong. The memory swelled up and took over every single sense in my brain, completely overpowered me. I lost all awareness of contemporary sensory experience. In the eyes of the world I'd turned into a senseless vegetable. All I could see, hear or touch was that frog in my memory. I no longer knew there was anything else.

"Simon was terrified. He unstrapped me and threw away his machine, pretended I'd just gone mad for no reason. The doctors at the hospital were baffled, tried all sorts of tests, but couldn't get any sense out of me. My parents were worried sick of course, they took care of me, fed me, bathed me, dressed me. I had no capacity to live, without their constant attention I'd never have survived."

"But it couldn't have lasted that long, not one charge of electric?"

"Oh, but it did, I was out of it for nearly a year. A whole year, all there was in my brain was this over-excited memory of a child holding a frog. It started to subside, gradually, and I had some real-time experiences, began to see, to hear, to talk, to eat and taste, I became almost human for minutes at a time, then the memory would come throbbing back and it'd just be the frog again.

"It's still there. Even now I get moments when I'm lost to the world, when I'm overcome by frog-memory. I had one while you were making coffee. That's why I decided to tell you. You're the only one I know who'd understand."

The bad news, of course, is that if a girl thinks she can tell you about something as intimate as the frog in her life, then it means she sees you as a friend and not a boyfriend. The border had shifted, we knew where we stood, or sat, Kelly would become my best friend in the whole wide world, but never my lover.

"I never grassed on Simon. No-one would benefit. He'd moved on to new experiments by then, a new girlfriend. He still came to see me, throughout my 'illness', but I don't know if that was because he still loved me or because he was scared he'd be found out. Probably the latter. I never told him about the frog, we never talked about what had happened, maybe he thought I didn't know. We, he, lost touch soon after.

"So that's me. That's fragile, scared, scarred, slightly mad me. I lost a year of my life, but so what, people lose time every day. What terrifies me is the thought that it might come back, a total relapse, and that would be it, the rest of my life just one recurring frog. Sometimes that scares me so much I just weep."

"I know," I said cradling her softly, "I've seen it."

She clutched me furiously tightly, weeping again. We sat like that for a long time, her holding on to me as if I was the only thing stopping her from falling off a cliff. Maybe, metaphorically, I was. The clock beside my bed said 2.59, but as I watched it clicked to 3.00. Kelly was still grabbing on to me, as if for dear life. I was subsumed in the intensity of the experience: the drip of wet tears on my T-shirt, the warmth of her slightly-sobbing breath, the frissle of her hair against my face, the smell of - well the smell of a Kelly close up - coffeeish breath, salty tears, pine-fresh hair, Kelly's body.

She slept over that night. Not in bed with me, but on the bed, fully-clothed, snuggled up close like twins in a womb. The only time we ever slept together. We rarely speak about that night, about the frog and Kelly's lost year, about her occasional relapses, about Simon. We rarely got that physically close again either.

As I say, Kelly remains my best friend. I'm godfather to her eldest and a regular visitor to her door. Sometimes even now I see her disappear, for a second, or a minute, and I know that the frog is back. Her husband doesn't notice, nor her children, maybe she'd drop something while she's affected and they'd notice that, but they'd never know the why. I'm still the only one she's ever told.

Each time it happens I close my eyes and pray, the only time I make any attempt at contacting a god, as I don't believe in one, but I pray non the less, that she'll come back. To date she always has.

I sometimes wonder what if it happened to me? If, not by mad-scientist-boyfriend's design, but a passing whisp of electricity, an excited spark leaping from a faulty kettle perhaps, chancing into my brain and leaving me living a life of just one moment, a memory from long ago repeating over and over and over until I died.

If I could choose the memory, which of course I couldn't, I'd remember that moment, as the clock clicked from 2.59 to 3.00. I'd remember Kelly, 3.00 a.m.