"She was wearing these new dungarees I'd bought her. OshKosh. I had a job working in a corner shop, after school, on Saturdays. Michelle and I had always worked, we'd never have had anything it we hadn't. I remember thinking how much those dungarees had cost and how the blood was never going to come out. My brother-in-law had just been killed by my sister and I was thinking about stain removal."

"The brain disassociates to stop us from going mad."

"You think I don't know that, Mr. Brodie?"

Shirley Morrison's toenails were painted with a pale polish and she was wearing a delicate gold chain around one ankle. Jackson remembered a time when only tarts and whores wore chains around their ankles. There used to be a prostitute who lived on the same street as Jackson when he was young. She wore emerald green eye shadow and red stilettos and had white, veiny legs. Did she wear an anklet? Did she have a name? Jackson used to run past her house in terror in case she came out and caught him because his mother told him that she was "a servant of Satan," which had confused him because "Satan" was the name of a dog – a big rottweiler – owned by a guy on the allotments.

Jackson hadn't thought about that street for a long time, a gloomy terrace with passages like tunnels that went through to a back alley. They'd moved to a better class of street when Jackson was nine. No whores hanging around on the doorstep, smoking their lungs out. Was Shirley Morrison married? She had a ring on her finger but it was neither a wedding ring nor an engagement ring, it was silver, Celtic or Scandinavian, what did that mean?

"When I picked Tanya up, Michelle laughed and said, 'She does go on, doesn't she?' Now that's disassociation."

''She must have had some reason for killing him," Jackson puz-zled, "even if it wasn't premeditated. Something must have triggered it."

It felt as if all the air in the office had been used up. It wasn't midday yet but it was already sweltering. Shirley's light brown hair was screwed up carelessly on top of her head and the fine hairs at the nape of her neck were dark with sweat. He wondered what she'd do if he invited her to lunch, a nice pub with a garden, or buy a sandwich and go for a walk by the river. It wouldn't be unprofessional, it would just be moving this appointment outside. Who was he kidding? His motives were entirely unprofessional.

If Josie died Jackson would get sole custody. Marlee wouldn't go to the other side of the world ("Lord of the Rings," she'd said to him, quite thrilled, as if Bilbo and Gandalf and the rest of their crew actually lived in New Zealand and were waiting for her to join their fellowship. She hadn't read the books, only seen the DVDs, which were far too scary for an eight-year-old in Jackson 's opinion, but not in the opinion of David Lastingham apparently).

For her part, of course, Josie had failed to keep any of the promises she had made – to love and honor him, to be faithful to him – he could still hear that little flutter of emotion in her voice when she said, "Until death us do part." They had opted for the Traditional wedding service. Now she was planning a tropical beach ceremony with a Maori gospel choir and homemade vows. She was going to marry that wanker and "start a new life."

Jackson wondered if he was capable of killing Josie. He was bet-ter placed than most people – he knew all kinds of ways to do it, it wasn't doing it that was the problem, not being found out, that was the thing. He wouldn't wait around for hours with an ax sitting in his lap. What was that Lizzie Borden rhyme? "Lizzie Borden took an ax, gave her mother forty whacks." If he killed Josie it would have to be done in a "calculated, cold-blooded killing" – fire, explosives, a gun. A gun for preference, an L96 Al sniper with a Schmidt and Bender sight, so you could be as far away as possible – he couldn't do an intimate killing, something close-up and personal like strangling or a knife, he couldn't be there, watching the blood stop pumping round her cheating heart, couldn't watch the life fade from her eyes. And not poison. Poison was for psychopaths and deranged Victorian women. Had he really been mugged the other night? Nothing had been taken from him, his wallet, his watch, his car, were all left behind, but then he'd fought back before the guy could take anything. In Jackson 's experience, muggers didn't usually try and smash your skull in. "There's a lot of bad people out there, sir," the DC ("DC Lowther, sir") who took his statement said. They'd sent a DC where they'd normally have sent a PC. Jackson supposed he should feel flattered. He remembered DC Lowther when he was an eager young recruit in uniform. "There's been a spate of mugging? recently, Inspector," DC Lowther said, and Jackson said, "It's just plain 'Mr. Brodie' now." It was funny, he'd never really been Mr. Brodie, he'd joined the army at sixteen and until then he'd just been Jackson, sometimes "Brodie!" from the male teachers. Then it was "Private Brodie" and so on up the ranks until he left the army and then he'd started again as "PC Brodie." He wasn't sure how he felt about being "plain Mr. Brodie."

"Do you have any enemies, sir?" DC Lowther asked hopefully.

"Not really," Jackson said. Just about everyone he'd ever met.

Jackson 's shirt was sticking to his skin, it was way too hot to be in an office.

"I don't know what triggered it," Shirley said. "She just went berserk."

There was always a trigger, there was a lot of things that the defense could have used – psychotic episodes, sleep deprivation, baby blues, shit childhood, self-defense (what about the bruise on her face?). "In court," Jackson said, "Michelle said that he woke the baby. The baby was asleep and Keith woke her up, that was the nearest she got to giving a motive." Jackson could imagine how that went down with the judge. She might as well have pleaded guilty. Michelle Fletcher hadn't run away or made up a story, she had simply waited to be found. By her sister.

If she had served two-thirds of her sentence Michelle Fletcher would have been back on the outside in 1989, at the age of twenty-eight. The same age Laura Wyre would be if she'd lived. Jackson would lay a bet that Michelle had been a model prisoner, trans-ferred to an open prison by '85, catching up with her exams probably, so she could start her "new life" when she came out. Like Josie. A fresh start, wiping out the past. Just like that. What was Michelle doing now? Shirley Morrison didn't know, of course she didn't know. That was why she was here.

"I promised Michelle I would look after Tanya," Shirley said, "and I would have done, of course I would have done, but I was only fifteen and social services decided our parents were unfit – which they were – and gave custody to Keith's parents. But they weren't much better. The last time I ever saw my sister was in the court the day she was sentenced. She refused to see us, knocked back all our visitor's orders, refused to read letters, there was nothing we could do about it. I could have understood if she didn't want to see Mum or Dad, they both died without seeing her again. But not to see me… I mean I didn't care that she'd killed Keith, she was still my sister, I still loved her." She shrugged and added, "Anyone's capable of killing, given the right circumstances." She was looking at that faraway world again, the one that existed on the other side of the office window, and Jackson supposed he could have said, "Yeah, I've killed people," but that didn't seem like the kind of dialogue he wanted to enter into at half past eleven on a Monday morning in these temperatures, so he said nothing at all.

"They told us when she was released," Shirley continued, "but she never got in touch. I don't know where she went or what she's doing now. In the end she got a new life and we were stuck with her old one. 'Murder' – it's such a stigma, isn't it? It's so… trashy. I wanted to go to medical school, be a doctor, but that was never going to happen, not after everything we went through." "And now you want me to look for your sister?" Shirley laughed as if he'd said something absurd, "God, no. Why would I want to look for Michelle when she's made it so obvious she doesn't want to be found? She doesn't care about me anymore. I don't want to find Michelle. I want to find Tanya."