Frank arched an eyebrow. “Not to labor the point,” he said, “but that’s what Detective Maddox and I are going after.”

“Yeah,” Sam said, without looking at him. “And if I find him fast enough, you won’t need to.”

“Better get a move on,” Frank said. He was still lying back on the sofa, watching Sam through lazy, narrowed eyes across the curls of smoke. “I’m aiming to go in Sunday.”

There was a second of absolute silence; even the wind outside seemed to have skidded to a stop. Frank had never mentioned a definite date before. In the corner of my eye the maps and photos on the table twitched and crystallized, unfurling into sun-glossed leaves, rippled glass, smooth-worn stone; turning real.

“This Sunday?” I said.

“Don’t give me that gobsmacked look,” Frank told me. “You’ll be fine, babe. And think of it this way: you won’t have to look at my ugly mug any more.” Right at that moment, this actually did feel like a pretty big plus.

“Right,” Sam said. He drained his coffee in long gulps and winced. “I’d better head.” He stood up and patted vaguely at his pockets.

Sam lives on one of those creepy housing estates out in the middle of nowhere, he was dropping with fatigue and the wind was picking up again, ripping at the roof tiles. “Don’t drive all that way, Sam,” I said. “Not in this weather. Stay here. We’ll be working pretty late, but-”

“Yeah, stick around,” Frank said, spreading his arms and grinning up at him. “We can make it a pajama party. Toast marshmallows. Play Truth or Dare.”

Sam took his coat off the back of the futon and stared at it as if he wasn’t sure what to do with it. “Ah, no; I’m not going home, sure. I’ll head into the squad for a bit, pull a few records. I’ll be grand.”

“Fair enough,” Frank said cheerfully, waving good-bye. “Have fun. Be sure and ring us if you find a prime suspect.”

I walked Sam downstairs and kissed him good night at the front door and he headed doggedly off towards his car, hands in his pockets and head bent hard against the wind. Maybe it was just the blast that funneled back up the stairwell with me, but without him my flat felt colder, barer somehow, a thin sharp edge in the air. “He was leaving anyway, Frank,” I said. “You didn’t have to be such a wankstain about it.”

“Possibly not,” Frank said, swinging himself vertical and starting to stack up the Chinese cartons. “But, as far as I can tell from the phone videos, Lexie didn’t use the term ‘wankstain.’ In the relevant circumstances, she used ‘git’-occasionally ‘big smelly git’-or ‘prat’ or ‘dickhead.’ Just something to bear in mind. I’ll do the washing up if you can tell me, without peeking, how to get from the house to the cottage.”

Sam didn’t try to make me dinner again, after that. He came in and out at weird hours, slept at his own place and said nothing when he found Frank on my sofa. Mostly he stayed just long enough to give me a kiss, a bag of supplies and a fast update. There wasn’t a lot to tell. The Bureau and the floaters had combed every inch of the lanes where Lexie took her late-night walks: no blood trail, no identifiable footprints, no sign of a struggle or a hiding place-they were blaming the rain-and no weapon. Sam and Frank had called in a couple of favors to keep the media from jumping all over this one; they gave the press a carefully generic statement about an assault in Glenskehy, dropped vague hints that the victim had been taken to Wicklow Hospital, and set up discreet surveillance, but no one came looking for her, not even the housemates. The phone company came back with nothing good on Lexie’s mobile. The door-to-door turned up blank shrugs, unprovable alibis (“… and then when Winning Streak was over the wife and I went to bed”), a few snotty comments about the rich kids up at Whitethorn House, an awful lot of snotty comments about Byrne and Doherty and their sudden burst of interest in Glenskehy, and no useful info at all.

Given their relationship with the locals and their general enthusiasm level, Doherty and Byrne had been assigned to go through a bazillion hours of closed-circuit TV footage, looking for regular unexplained visitors to Glenskehy, but the cameras hadn’t been positioned with this in mind and the best they could come up with was that they were fairly sure no one had driven into or out of Glenskehy by a direct route between ten and two on the night of the murder. This made Sam start talking about the housemates again, which made Frank point out the multiple ways someone could have got to Glenskehy without being picked up on CCTV, which made Byrne get snippy about suits who swanned down from Dublin and wasted everyone’s time with pointless busywork. I got the sense that the incident room was blanketed by a dense, electric cloud of dead ends and turf wars and that nasty sinking feeling.

Frank had told the housemates that Lexie was coming home. They had sent her things: a get-well card and half a dozen Caramilk bars, pale-blue pajamas, clothes to wear home, moisturizer-that had to be Abby-two Barbara Kingsolver books, a Walkman and a pile of mix tapes. Even aside from the fact that I hadn’t seen a mix tape since I was about twenty, these were kind of hard to put your finger on-there was Tom Waits and Bruce Springsteen, music for late-night jukeboxes on long strange highways, in with Edith Piaf and the Guillemots and some woman called Amalia singing in throaty Portuguese. At least they were all good stuff; if there had been any Eminem on there, I would have had to pull the plug. The card said “Love” and the four names, nothing else; the briefness made it feel secretive, fizzing with messages I couldn’t read. Frank ate the Caramilks.

The official story was that the coma had knocked out Lexie’s short-term memory: she remembered nothing about the attack, very little about the days before. “Which has side benefits,” Frank pointed out. “If you fuck up some detail, you can just look upset and murmur something helpless about the coma, and everyone’ll be too embarrassed to push you.” Meanwhile, back at the ranch, I had told my aunt and uncle and my friends that I was going off to do a training course-I kept it vague-and wouldn’t be around for a few weeks. Sam had smoothed over my exit from work by having a chat with Quigley, the Murder squad’s resident mistake, and telling him in confidence that I was taking a career break to finish my degree, which meant I would be covered if anyone spotted me hanging around town looking studenty. Quigley basically consists of a large arse and a large mouth, and he never liked me much. Within twenty-four hours it would be all over the grapevine that I was taking time out, probably with a few flourishes (pregnancy, psychosis, crack addiction) thrown in for good measure.

By Thursday Frank was firing questions at me: where do you sit for breakfast? where do you keep the salt? who gives you a lift into college on Wednesday mornings? what room is your supervisor’s office? If I missed one, he zeroed in on that area, worked around it from every angle he had-photos, anecdotes, phone video, audio footage of interviews-till it felt like my own set of memories and the answer rolled off my tongue automatically. Then he went back to the question barrage: where did you spend the Christmas before last? what day of the week is your turn to buy food? It was like having a human tennis-ball machine on my sofa.

I didn’t tell Sam this-it made me feel guilty, somehow-but I enjoyed that week. I like a challenge. It did occasionally occur to me that I was in a deeply weird situation and that it was only likely to get weirder. This case had a level of Möbius strip that made it hard to keep things straight: Lexies everywhere, sliding into each other at the edges till you started to lose track of which one you were talking about. Every now and then I had to catch myself back from asking Frank how she was doing.