He bought her a chickinlickin burger ("with fries," she begged) and a Coke. For fast food it seemed very slow and Theo wondered if anyone monitored the service in these places. Most of the people working here seemed to be children – Australian children at that.

They had been gone a lot longer than ten minutes. If Jackson was back he would be sending out search parties by now. As if the very thought of his name conjured him up, Jackson suddenly appeared out of a crowd of jostling foreign students. He looked slightly wild and grabbed hold of Marlee's arm so that she squealed in protest, "Daddy, mind my Coke."

"Where've you been?" Jackson shouted at her. He glared at Theo. What a cheek, when all Theo was doing was looking after the girl, which was more than her parents were doing.

"I'm babysitting," Theo said to Jackson, "not cradle snatching."

"Right," Jackson said, "Of course, I'm sorry, I was worried."

"Theo's looking after me," Marlee said, taking a huge bite out of her burger, "and he bought me fries. I like him."

When Theo returned along St. Andrews Street the girl with the custard-yellow hair was no longer there and he worried that she might never be there again. Because that was how it happened: one moment you were there, laughing, talking, breathing, and the next you were gone. Forever. And there wasn't even a shape left in the world where you'd been, neither the trace of a smile nor the whisper of a word. Just nothing.

Your soft palate looks very inflamed," Sharon murmured. "Does it hurt?"

"Nugh, nurnh."

"I suspect you're blowing out an abscess, Jackson."

Officially she was "Miss S. Anderson, BDS, LDS," and he'd never been invited to call her by her Christian name, although she was free enough with his own first name. Doctors, bank managers, complete strangers, all used first names now. It was one of Binky Rain's bugbears. "And I said to the man in the bank ["men in the benk"] – a cashier- 'Excuse me, young man, but I don't recall us having been introduced. As far as you're concerned, my name is Mrs. Rain, and I don't give a damn what yours is.'" Binky Rain made "cashier" sound like something you wouldn't want to pick up on the sole of your shoe.

He felt absurdly vulnerable, lying there in the chair, prostrate and helpless, subject to the whims of Sharon and her silent dental nurse. Both Sharon and the dental nurse had dark, enigmatic eyes, and they had a way of looking at him indifferently over their masks as if they were contemplating what they might do to him next, like sadistic belly dancers with surgical instruments.

Jackson tried not to think about this, nor about that scene in Marathon Man, and instead worked on conjuring up a picture of France. He could grow vegetables, he'd never grown a vegetable in his life, Josie had been the gardener, he'd carried out her orders, Dig this, move that, mow the lawn. In France, the vegetables would probably grow themselves anyway. All that warm fertile soil. Tomatoes, peaches. Vines, could he grow vines? Olives, lemons, figs – it sounded biblical. Imagine watching the tendrils creeping, the fruit plumping, oh God, he was getting an erection (at the idea of vegetables, what was wrong with him?). Panic made him swallow and gag on his own saliva. Sharon returned the chair to an upright position and said, "All right?" her head cocked to one side in an affectation of concern while he choked noisily. The silent dental nurse handed him a plastic cup of water.

"Soon be done now," Sharon lied, tilting him backward again, Jackson concentrated on something unpleasant this time. Laura Wyre's body. Felled in her tracks, like an animal, like a deer.

Mr. Wyre, where is he? It was an odd-sounding question – wouldn't it be more normal to say, "Where's Mr. Wyre?" Did the killer actually say that? What if he'd said, "Miss Wyre" or "Ms. Wyre"? Could Moira Tyler (the only person the killer spoke to) have misheard him? In the chaos of the moment – but then the moment wasn't chaotic at that point. He was just a guy in a yellow golfing sweater asking the whereabouts of one of the solicitors.

And Laura's own private life, was it as transparent as it appeared to be? A sacrificial virgin. Was she a virgin? Jackson couldn't remember reading that in the autopsy report. Theo believed she was, of course. Jackson could imagine that Marlee could be married and divorced three times and have ten children and he would still believe that she was a virgin.

The press had loved Laura's blamelessness. It was always so much better when it was a nice middle-class girl with sound habits and educational aspirations who got topped rather than some prostitute or tarty unemployed teenager (the Kerry-Anne Brockleys of this world). But who was to say that Laura Wyre didn't have secrets? An affair with a married man that she didn't want to hurt her father with, perhaps. Or had she innocently acquired a stalker, some shitty little pervert who'd become fixated on her? Maybe she was pleasant to him (sometimes that was all it took) and he'd become deluded, imagining that she was in love with him, that they had some cosmic thing going on between them. There was a word for that but Jackson couldn't remember it, some syndrome, not Munchausen. There were only four options. The guy either knew Theo personally or was a stranger to him. He either knew Laura personally or was a stranger to her. Erotomania – that was it. It sounded like a bad Dutch porn movie.

There was that survey, years ago, that found that women didn't feel threatened by a man carrying the Guardian or wearing a CND badge. Jackson had wondered at the time how many rapists started carrying a Guardian around with them. Look at Ted Bundy. Stick your arm in a plaster cast and women think you're safe. No woman was ever truly safe. It didn't matter if you were as tough as Sigour-ney Weaver in Alien Resurrection or Linda Hamilton in Terminator 2. because wherever you went there were men. Crazy men. The thing he liked about tough women such as Ripley and Sarah Connor (and yes, he knew they were fictional) was that it didn't matter how kick-ass they were, their motives stemmed from a kind of maternal love, a maternal love for the whole world. No, don't go there, Jackson, don't think about Sarah Connor. Think about something bad, think about the exhaust on your car that needs fixing, think about something boring. Golf.

"I've cleaned out the pus, Jackson," Sharon whispered softly, "and I'm going to put a dressing on, but we can't keep on treating the symptoms. We have to eliminate the cause. The root."

Laura's closest friends at sixth-form college had been Christina. Ayshea, Josh, Joanna, Emma, Eleanor, Hannah, and Pansy. Jackson knew this because Theo had a handy wall chart with the heading STUDENTS at laura's college, as opposed to another chart, laura's FRIENDS outside OF college (scuba-diving club, people from the pub she'd worked with, and so on), and yet a third chart for LAURA'S casual acquaintances (which was basically anyone whose path had ever crossed hers).

students at laura's college was a numbered list, the numbers indicating the closeness of the friendship – number one being her best friend and so on. Every student at the college was listed. How much time had Theo spent trying to decide if someone should be ranked 108 or 109 on the list? He hadn't even done the list on a computer but had laboriously handwritten all the names. The guy was crazy.

The friends were also color coded by sex – blue ink for the girls, redfor the boys, which made it easy to see that Laura's closest friends were mostly girls. The top ten were all blue with only two excep-tions-Josh and Tom. Laura Wyre had obviously been a girl's girl, one destined never to become a woman's woman. Toward the end of the list there was an almost solid phalanx of red names – great clus-ters of boys, most of whom Laura Wyre had probably never even noticed, let alone spoken to. The use of the red ink made the boys stand out and look more dangerous, or incorrect somehow. Jackson had a sudden image of his essays at school, spiderwebbed with the angry red-ink annotations of his teachers. It was only after he left school and joined the army that he discovered he was intelligent.