Kevin was slumped against our railings, looking the way he used to when we were kids and he got left behind for being too little, except that now he had a mobile and he was texting away at top speed. “Girlfriend?” I said, nodding at the phone.

He shrugged. “Sort of, I guess. Not really. I’m not into settling down yet.”

“That means you’ve got a few of them on the go. Kev, you dirty dog.”

He grinned. “So? They all know the story. They’re not into settling down either; we’re just having a laugh. Nothing wrong with that.”

“Nothing at all,” I agreed, “except I thought you were wrangling Ma for me, not playing Fingers of Love with today’s laugh. What happened to that?”

“I’m wrangling her from here. She was doing my head in. If she’d tried to go across to the Dalys, I’d’ve caught her.”

“I don’t want her ringing the world and his wife.”

“She won’t ring anyone, not till she’s called round to Mrs. Daly and got all the sca. She’s doing the washing up and giving out. I tried to give her a hand and she threw a freaker because I put a fork in the drainer wrong way up and someone was gonna fall on it and lose an eye, so I split. Where were you? Were you in with Mandy Brophy?”

I said, “Let’s say you wanted to get from Number Three to the top of the Place, but you couldn’t go out the front door. What would you do?”

“Back door,” Kevin said promptly, going back to texting. “Over the garden walls. Did it a million times.”

“Me too.” I aimed a finger along the line of houses, from Number 3 up to Number 15 at the top. “Six gardens.” Seven, counting the Dalys’. Rosie could be still waiting for me in any one of them.

“Hang on.” Kevin looked up from his phone. “Do you mean now, or way back when?”

“What’s the difference?”

“The Halleys’ bloody dog, that’s the difference. Rambo, remember him? The little bastard bit the arse out of my trousers that time?”

“Jesus,” I said. “I’d forgotten that little fucker. I drop-kicked him once.” Rambo was, naturally, some kind of terrier-based mutt that weighed about five pounds soaking wet. The name had given him a Napoleon complex, complete with territorial issues.

“Now that Number Five’s those eejits and their Teletubby paint, I’d go the way you said”-Kevin pointed along the same line I’d drawn-“but back then, with Rambo waiting to rip me a new one, not a chance. I’d go that way.” He turned, and I followed his finger: down past Number 1, along the high wall at the bottom of the Place, up the even-numbered gardens, over the wall of Number 16 to that lamppost.

I asked, “Why not just come back over the bottom wall and straight up the road? Why would you be arsed with the gardens on our side?”

Kevin grinned. “I can’t believe you don’t know this shit. Did you never go throwing rocks up at Rosie’s window?”

“Not with Mr. Daly in the next room. I like having testicles.”

“I was buzzing off Linda Dwyer for a while, when we were like sixteen-remember the Dwyers, in Number One? We used to meet in her back garden at night, so she could stop me putting my hand up her top. That wall”-he pointed to the bottom of the road-“on the other side, it’s smooth. No footholds. You can only get over it at the corners, where you can use the other wall to pull yourself up. That takes you into the back gardens.”

“You’re a fountain of knowledge,” I said. “Did you ever get into Linda Dwyer’s bra?”

Kevin rolled his eyes and started explaining Linda’s complex relationship with the Legion of Mary, but I was thinking. I had a hard time picturing a random psycho killer or sex attacker hanging around back gardens on a Sunday night, hoping forlornly that a victim would stroll by. If someone had nabbed Rosie, he had known her, he had known she was coming, and he had had at least the basics of a plan.

Over the back wall was Copper Lane: a lot like Faithful Place, only bigger and busier. If I had wanted to arrange any kind of clandestine meeting or ambush or what-have-you along the route Kevin had pointed out, especially a clandestine meeting that might involve a struggle or a body dump, I would have used Number 16.

Those noises I had heard, while I waited under the lamppost shifting from foot to foot to keep from freezing. A man grunting, stifled squeaks from a girl, bumping sounds. A teenage guy in love is a walking pair of nads wearing rose-colored glasses: I’d taken it for granted that love was everywhere. I think I believed Rosie and I were so wild about each other that it got in the air like a shimmering drug, that night when everything was coming together, and swirled through the Liberties sending everyone who breathed it into a frenzy: wrecked factory workers reaching for each other in their sleep, teenagers on corners suddenly kissing like their lives depended on it, old couples spitting out their falsies and ripping off each other’s flannel nighties. I took it for granted that what I was hearing was a couple doing the do. I could have been wrong.

It took a mind-bending effort to assume, just for a second, that she had been coming to me after all. If she had, then the note said she had very probably made it along Kevin’s route as far as Number 16. The suitcase said she had never made it out.

“Come on,” I said, cutting off Kev, who was still going (“… wouldn’t have bothered, only she had the biggest rack in the…”). “Let’s go play where Mammy said we shouldn’t.”

Number 16 was in even worse shape than I’d thought. There were big gouges all the way down the front steps where the builders had dragged the fireplaces away, and someone had nicked the wrought-iron railings on either side, or maybe the Property King had sold them too. The whacking great sign announcing “PJ Lavery Builders” had fallen down the well by the basement windows; nobody had bothered to retrieve it.

Kevin asked, “What are we doing?”

“We’re not sure yet,” I said, which was true enough. All I knew was that we were following Rosie, feeling our way step by step and seeing where she led us. “We’ll find out as we go, yeah?”

Kevin poked the door open and leaned forward, gingerly, to peer in. “If we don’t end up in hospital first.”

The hallway was a tangle of crisscrossing shadows, layered half a dozen deep where faint light seeped in from every angle: from the empty rooms with their doors pulled half off, through the filthy glass of the landing window, down the high stairwell along with the cold breeze. I found my torch. I may be out of the field, officially, but I still like being ready for the unexpected. I picked my leather jacket because it’s comfortable enough that it almost never comes off, and it has enough pockets to hold all the basics: Fingerprint Fifi, three small plastic evidence bags, notebook and pen, Swiss Army knife, cuffs, gloves, and a slim, high-powered Maglite. My Colt Detective Special goes in a specially made harness that keeps it snug at the small of my back, under my jeans waistband and out of sight.

“I’m not joking,” Kevin said, squinting up the dark stairs. “I don’t like this. One sneeze and the whole place’ll come down on top of us.”

“The squad has a GPS tracker implanted in my neck. They’ll come dig us out.”

“Seriously?”

“No. Man up, Kev. We’ll be fine.” And I switched my torch on and stepped into Number 16. I felt the decades’ worth of dust specks hanging suspended in the air, felt them shift and stir, rising up to whirl in cold little eddies around us.

The stairs creaked and flexed ominously under our weight, but they held. I started with the top front room, where I had found Rosie’s note and where, according to Ma and Da, the Polish boys had found her suitcase. There was a great jagged hole where they had ripped out the fireplace; the wall around it was crowded with faded graffiti explaining who loved who, who was gay and who should fuck off. Somewhere on that fireplace, on their way to someone’s Ballsbridge mansion, were my initials and Rosie’s.