When they bring Caitlin home, I'm standing by the side of the road. Nobody has told me when she will be discharged from the hospital, but I have a premonition and have been standing there all morning. I wander about a bit, nip the dead heads out of the geraniums on the windowsills with my barely healed fingers, and grind blades of grass, green again after the rain, into brown shreds. Because of the dense cloud, it looks as if the house, covered in climbing roses, and the convent further down the hill are sheltered under a gigantic waterproof tent. What strikes me most is that the shutters are open: they've been closed all summer to keep out the heat. Now, moist air is blowing in through them.

When the ambulance drives past, I'm standing with my back to the house, on the inside of the bend. Because of the rustling of the wind in the trees, I haven't heard it coming. It's driving up the slope slowly from around the curve, the engine rumbling in low gear. I have plenty of time to look in through the windows. Caitlin is not on the stretcher in the back, as she was three weeks ago, when she was being carried away with sirens screaming. She sits on the driver's right, confidently looking ahead, as if she is used to travelling in ambulances. ('I can't figure you out,' I said to her once. She turned half towards me and answered: 'We were forced to move time and again. That makes you forget how to make close friends.')

The driver takes the bend cautiously. I follow their movement not just with my eyes and my head, but with my whole body, slowly turning, my arms hanging limp by my sides and my chin sticking out a little. Before I quite realise, we are looking into each other's eyes. I want to nod, blink my eyes at her, call out something, but my face turns to stone. She looks at me the way you look at a passing building, or at a pedestrian you don't know and take no notice of. She looks normal, no different from usual, except for the yellowish tinge of her face. She is sitting up straight, stretching her neck out the way some waterbirds do just before flying off. I know how she talks, and how she moves when she says something. I can see the way she will look at something, blink, turn round and say: 'What did you say?' She seems like quite an ordinary girl, the way she is sitting there, a girl who rides her bike down a slope and climbs back up on foot, a girl who, on warm days, walks up to her knees into the water of the pond and suddenly, unexpectedly, with a shout, throws herself full length into the water. A girl who yells: 'Shit, the brakes aren't working!' when she is driving through the hills without her mother knowing.

Our eye contact lasts no longer than half a second — my eyes instantly focus on a point in the distance and she looks down to the road surface — but it feels like an eternity. I become totally conscious of the way I am standing here, in jeans, bare feet in my shoes, craning my neck to see her properly. My hands are still bandaged in a few places. I rub my fingers together to feel the pain, but the wounds are dry, and nearly all have healed over. I am only aware of a kind of insensitivity round my fingernails, and a velvety hypersensitivity where new skin has grown. Suddenly I know why I am standing there so openly: I want to behave as if I am not ashamed of what has happened.

As soon as the white ambulance has disappeared behind the trees, I walk around the house. I say nothing to my mother, who is bringing the garden chairs onto the back porch and covering the cushions with plastic. I go inside and upstairs to the bedroom that was once my grandfather's. I shut the door behind me, and, when I hear my mother coming inside, turn the key. The two suitcases which I have been packing earlier this morning are standing in the middle of the room. I pick them up and put them next to the wall. Next I try to shift the writing desk under the skylight without making a noise, but I can hardly manage: the timber floor is uneven and the desk heavy. The legs make a scraping noise. I climb onto the table and, through the gap in the foliage of the treetops, I look at the courtyard in front of the convent building.

I'm in time. The ambulance is just arriving. It slows and stops. The driver gets out, jumps almost, as if to show how healthy he is. Half skipping, he walks round the car and opens Caitlin's door. First he brings out two grey crutches and leans them against the open car door. He offers his left arm. Caitlin's hand appears on his white sleeve. As I see the movement of the hand to the sleeve, the hair on the back of my neck stands on end. For a moment it is as if I feel her hand on my arm. I know her hands are never clammy, but always cool and dry, as if she regularly washes them under the cold tap. I have touched them nearly every day, every time we went down to the town along the path that shepherds once used, and took the shortcut, clambering over Challon's Bluff.

He helps her get out. While she is laboriously busy moving herself out of the car, I can see nothing unusual. For long seconds I believe that everything has actually turned out all right. But then she makes a quarter turn. She now has her face towards me, throws her head back lightly and stays motionless for a moment. Of course she knows I'm here, standing on the table watching her. I can't see the expression on her face, because the distance is too great. It starts raining gently. A flight of doves drifts in, as if lost, and lands awkwardly a few metres behind her. She takes a crutch under each arm and places her legs apart a little. Now I can see clearly that her left foot is gone.

* * *

'Lucas!' my mother calls from downstairs.

'Yes,' I reply without moving. Caitlin keeps looking in my direction while the driver reaches inside the car to get her luggage. He brings out a blue striped sports bag, is about to put it down but hesitates and, after a few quick words from Caitlin, slings it over his shoulder by its strap. He disappears half into the car again and produces two bunches of flowers.

'I know what you're doing,' my mother calls. I hear her coming up the stairs. Like a cat, I jump from the table. Using every last ounce of strength, I lift and put it back in its place without letting it touch the floor. There are two books on it, great hefty novels which my grandfather must have been reading in the long months before his death. They have shifted, and I put them back where they were. Before my mother gets to the door I turn the key again. She comes in, her hands still wet from the rain on the garden chairs, quickly glances round the room and smiles.

'I could have sworn you were standing on the table,' she says and sits down on the edge of the unmade bed. She dries her hands on her shirt and gets a packet of cigarettes out of the breast pocket.

'I heard she'll be allowed to go home soon,' she says, flicking a metallic coloured lighter. With her head she gestures towards the skylight. 'It's as well we are leaving. There is still such a lot of gossip down there. I am so fed up with this bloody little town. Perhaps they will have forgotten about it all by next summer.'

I say nothing, can say nothing, because all this time I see the amputated leg in front of me and realise that for three weeks I have refused to think about this scene. In my head I become aware of a strange sound that wasn't there before. It's like a Chinese orchestra with lots of bells, and then it changes into a buzzing noise. I sit down so I'll hear it less.

'How is the...