Then he said, 'You miss everything.' Something terrible happened to his voice. It sounded like tape gone slurry from dirty tapeheads. 'You miss voices. You miss air. You try to breathe and there's no air. There's no taste, you're not hungry, you don't want to eat. You miss food. And colour. There's no colour. You miss having a life. You get so bored being yourself. A self just keeps asking: What do I think about next? What do I do next? And the answer always comes back: Nothing.'

They heard a door open. Margaret, Maggie came back. Michael could tell from her face: it was kept smooth and bland, but the smile was just a little fixed, and the eyes seemed to be saying no, not again, no not again, and they looked at Mark with sadness. Mark had tested positive. She would have done a T-cell count as well and would know: this is a dying man.

All she said was: 'All right, Mark, we're going to take the second sample now. Are you sure you want to go ahead?'

'I believe that is what Michael asked.'

Margaret glanced at Michael. 'Michael only wants to help you. Do you still want a second sample?'

'It's why I'm here,' replied Mark, detached.

You, commanded Michael to the Angel. You Mark are free from disease. You virus, commanded Michael, you the virus just seethe out of his blood.

I cast you out.

Maggie took Mark's arm as she led him to the cubicle, and her face was silently looking into his. Still everyone's mother, eh Bottles?

The telly battered on, booming about oven-ready chips. Jeez, thought Michael, all I want to do is sleep. What a leaden stupid unhelpful thought: life is strange.

Mark came back, and moved his chair away from Michael and the cushions made a squishy sound like a sigh. Mark reached into the plastic bag and pulled out an orange.

Mark's mouth lunged forward as he bit into the orange. Almost clear juice, with a bit of pulp, poured down his chin. Mark's eyes closed with pleasure.

Then he reached into a bag and pulled out a photograph. There hadn't been a photograph in the bag before.

It was an ordinary snap of a solid-looking middle-aged man with white hair.

'This is Robert,' Mark said. 'I never told you about him.' His thumb moved over the face. 'He was rather discreet. He was married, and a bit old-fashioned. RAF. When I got too ill, I told him I was fed up being his mistress.'

'Did he know you were HIV?'

There was a long pause. 'Yes.'

Michael looked at the face in the photo more closely. It was kindly, dignified, direct. That added up too.

Mark reached into the plastic bag and pulled out one of the very first Sony Walkmans, clunky and black, with the usual tangle of wires and earphones. Mark said nothing, but punched buttons.

From the distanced high singing, Michael knew. Mark's favourite opera: Der Rosenkavalier. Mark closed his eyes and ruminated on another section of orange.

Time passed. The cassette finished with a click.

Mark asked, 'Do I have to stay for the second result?'

Michael was surprised and slightly hurt that Mark didn't want to know. 'I'm afraid so. If you go, the samples will disappear.'

Mark rolled his eyes. 'Oh, God! That means she'll come out all worried and want to counsel me. And if the result is different then she'll want to take a third sample.' He put his head in his hands. 'I don't suppose it occurred to you that I've been through all this once before and that I never, ever wanted to go through it again?'

Mark's eyes glared up at him from under the bushy eyebrows. In life, Mark had never been this angry with Michael.

'It didn't really, no, I'm sorry.'

'If you want to have a fuckfest, you'll just have to take a few risks like everyone else, except that you never had the stomach for risk.'

Michael didn't know what to say. Mark turned the cassette over and went on listening to opera.

Finally, Margaret came back. Michael noticed that she had tiny feet. They gave her a delicate, slightly Chinese walk. Her face had gone splotchy. As she approached, she placed her hands either side of her mouth, as if to hold her face in place. 'Mark. I hardly know what to say.'

Mark stood up and began to wind the earphones around the Walkman. The opera kept playing.

Margaret reached out towards him and gripped his arm. 'Michael told me you are worried about inconsistent results. I'm afraid that the first test was positive and the second is negative. It's not usual, but it does happen. I'm so sorry. I'm afraid we'll need to take the test again.'

'That won't be necessary. That is all the result we need, thank you very much.' He jammed the singing Walkman into the bag.

'Mark, you can come in tomorrow, if you like.'

The tumble of rocks looked back at her. 'That won't happen. I am very, very sorry that Michael put you to all this trouble. I'm going to ask you not to worry me, or to try to rectify the situation. Thank you for your concern.' He turned and strode away on long legs.

Margaret followed. 'We might prove there is nothing wrong! There are treatments now, treatments that work!'

Thank you!' bellowed Mark and let the door fall shut after him.

Michael stood up to go, sick at heart.

Maggie intercepted him. 'Michael, the first test showed almost no T-cells at all. He is already very sick. Michael, I don't know what your relationship is, excuse me, but should you have the test too?'

'No,' said Michael, suddenly bitter. 'I never slept with him.'

He died and I was in America. Michael's face crumpled and his eyes went bleary, and to escape he pushed the door open with his bum.

'Oh love,' said Margaret.

You think I'm a good person. You think I'm someone who's done all he can to help someone else.

'Give me a call! Tell him we can help him!'

That's the last Michael saw of her, in her Chinese shirt, reflecting in several directions as the door of her clinic swung shut. How is it that you care, Maggie? How is it than anyone cares?

Mark was two streets away, waiting by the car. He was staring up at the sky and listening to his Walkman. It still wheedled out Rosenkavalier. Shrill distant women's voices sang their farewells. Just for once, in London, there were stars.

'Can you send me back now?' Mark asked, without looking at Michael. He was quite calm, angry no longer, but his cheeks and mouth were covered with an even, glossy coating of tears.

'You could stay,' offered Michael.

Mark turned and looked at him with determined eyes. 'This is unbearable,' he said.

'Look Mark, I'm sorry for all of this; I shouldn't have done it this way. But if you stay, you could listen to music, you could go back to Robert, you could live.'

'It's unbearable, because once you're there,' Mark flung a hand up towards the sky, 'you don't really want to come back. You had no business bringing me back.'

'Just try, for a day or two?'

'I died Michael. I made them withhold treatment. Dying took hours, and I couldn't move or even see, but I could still think, and I had to think my way through dying. I had to work at it, it was an achievement. Can you please send me back now?'

'All right,' sighed Michael.

Mark made to put Robert's photograph into his pocket and then seemed to remember he could not take it with him. He put it back into the plastic Sainsbury's bag.

The great stone face turned once more to Michael. 'Don't do this to anyone else,' Mark said.

'Get ready then.'

'I am ready.'

'Goodbye, then.'

God, this was awful, it was like killing someone.

'Goodbye,' whispered Mark, his expression softening. His cheeks were pink and freckled and he reminded Michael of how he had looked at Sussex.

The singing of the Walkman stopped. Air closed over Mark like a lake and he was gone.

Michael was alone. Inside the bag, there was only the newspaper, and the orange, whole and uneaten.