I run into the arms of Andy's parents walking with the dogs near the ornamental ponds and it seems like an age before I can tell them what's happened because my voice won't work and I can see the fear in their eyes and they're asking, "Where is Andrew? Where is Andrew?" and eventually I can tell them and Mrs Gould gives a strange little shuddering cry and Mr Gould tells her to get the people in the house and phone for an ambulance and runs away down the path towards the river with the four Golden Labradors barking excitedly behind him.

I run to the house with Mrs Gould and we get everybody — my mum and dad and the other guests — to come down to the river. My father carries me in his arms. At the riverside we can see Mr Gould on his stomach out on the ice, pushing himself back from the hole in the river; people are shouting and running around; we head down the river towards the narrows and the gorge and my father slips and almost drops me and his breath smells of whisky and food. Then somebody calls out and they find Andy, round the bend in the river, down where the water reappears from a crust of ice and snow and swirls, lowered and reduced, round the rocks and wedged tree-trunks before the lip of the falls, which sound muted and distant today, even this close.

Andy's there, caught between a snow-covered tree-trunk and an iced-over rock, his face blue-white and quite still. His father splashes deep into the water and pulls him out.

I start crying and bury my face in my father's shoulder.

The village doctor was one of the house guests; he and Andy's father hold the boy up, letting water drain from his mouth, then lay him down on a coat on the snow. The doctor presses on Andy's chest while his wife breathes into the boy's mouth. They look more surprised than anybody when his heart restarts and then he makes a gurgling noise in his throat. Andy is wrapped in the coat and rushed to the house, submerged to the neck in a warm bath and given oxygen when the ambulance arrives.

He'd been under the ice, under the water, for ten minutes or more. The doctor had heard about children, usually younger than Andy, surviving without air in cold water, but never seen anything like it.

Andy recovered quickly, sucking on the oxygen, coughing and spluttering in the warm bath, then being dried and taken to a warmed bed and watched over by his parents. The doctor was worried about brain damage but Andy seemed just as bright and intelligent afterwards as he'd been before, remembering details from earlier in his childhood and performing above average in the memory tests the doctor gave him and even doing well in school when that started again after the winter break.

It was a miracle, his mother said, and the local newspaper agreed. Andy and I never did get properly told off for what happened, and he hardly ever mentioned that day to me unless he had to. His father didn't like talking about it much either and used to be slightly dismissive and jokey about it all. Mrs Gould gradually talked less about it.

Eventually it seemed it was only I who ever thought about that still, cold morning, recalling in my dreams that cry and that hand held out to me for help I could not, would not give, and the silence that followed Andy disappearing under the ice.

And sometimes I felt he was different, and had changed, even though I knew people changed all the time and people our age changed faster than most. Even so, I thought on occasion there had been a loss; nothing necessarily to do with oxygen starvation but just as a result of the experience, the shock of his cold journey, slipping away beneath the grey lid of ice (and perhaps, I told myself in later years, it was only a loss of ignorance, a loss of folly, and so no bad thing). But I could never again imagine him doing something as spontaneously crazy, as aggressively, contemptuously fate-tempting and unleashed as running out across the frozen ice, arms out, laughing.

You're already wearing your moustache and wig and glasses and you have clip-on sunshades over the lenses because it is quite a bright day. You ring the doorbell, watching down the drive for any cars while you pull on your leather gloves. You're sweating and nervous and you know you're out on a limb here, you're in the process of taking some terrible risks and the luck, the flow that comes from being justified and in tune and not taking too much for granted, not being contemptuous or disrespectful of fate; all that's in danger here because you're pushing the envelope, you're maybe relying on one or two too many things going perfectly. Even getting it all set up to get you this far may have taxed your fortune to the limit already and there's still a long way to go. But if you're going to fail you'll do it full-face on, not flinching, not whining. You've done more than you thought you'd ever get away with and so in a sense it's all gain from here, in fact it's been all gain for some time and so you can't complain and you don't intend to if fate deserts you now.

He comes to the door just like that; no servants, no security phone, and that by itself gives you the green light; you haven't the time for any finessing so you just kick him in the balls and follow him inside as he collapses, foetal on the floor. You close the door, take off your glasses because your vision is so distorted, and kick him in the head; far too softly, then still not hard enough, as he scrabbles round on the floor, one hand at his crotch and the other at his head, making a spitting, wheezing noise. You kick him again.

This time he goes limp. You don't think you've killed him or severed his spine or anything but, if you have, that can't be helped. You make sure he can't be seen from the letter flap, which is covered by a sealed box, then you look round the hall. Golf umbrella. You take that. Still nobody coming. You walk quickly through, see the kitchen and go in there, pulling down the Venetian blinds. You find a breadknife but you keep the umbrella too. You find some tape in a kitchen drawer and go back to the front hall, turning him round so that you're between him and the door. You tie his hands and wrists together. He's wearing expensive-looking slacks and a silk shirt. Crocodile slip-ons and monogrammed socks. Manicure and a scent that you don't recognise. Hair looks slightly damp.

You take off both his shoes and stuff both socks into his mouth; they're silk, too, so they ball up very small. You tape his mouth closed, put the roll of tape in one pocket, then leave him there to search the rest of the house, pulling down the blinds in each room as you go. In the kitchen again, you find the door to the cellar. On the first floor you hear music and the sounds of water.

You creep along to an open doorway. Bedroom; probably the master bedroom. Brass bed; huge, maybe even gold-plated. Disturbed bedclothes, broad sunlit balcony beyond windows and pastel-pink vertical blinds. The sounds are coming from the en-suite bathroom. You go into the bedroom, checking the position of the mirrors; none of them ought to show you to anybody in the bathroom. You're listening as you approach the bathroom door. The music is loud. It's a Eurythmics song called Sweet Dreams are Made of This. A power cable stretches from a socket in the wall into the bathroom. That's interesting.

The voice sings along with the song, then turns into a hum. Your heart sinks. You were hoping he was alone in the house. You look through the crack at the door hinge. The bathroom is big. In one corner there is a sunken Jacuzzi with a young person in it, moving sinuously in the bubbling waters. Caucasian, with short black hair. You can't tell whether the person is male or female. The research you did on Mr Azul didn't cover his sexuality.

The ghetto-blaster lies less than a metre away from the lip of the Jacuzzi. There is at least another couple of metres of flex coiled on the floor.