I closed the door again. “All right,” I said. I let myself slump back against the wall and tried to squeeze tension out of my shoulder. “All right. Here’s what I suggest. We’ll need to spend the next week or so investigating Conor Brennan, to waterproof our case—that’s assuming he’s our man. I suggest that, during that time, you and I also conduct a parallel investigation into Pat Spain. Superintendent O’Kelly would like that idea even less than I do—he’d call it a waste of time and manpower—so we won’t make a song and dance about it. If and when it does come up, we’re just making sure Brennan’s defense isn’t going to find anything on Pat that they can use as a red herring in court. It’ll mean a lot of very long shifts, but I can handle that if you can.”

Richie already looked ready to fall asleep standing up, but he was young enough that a few hours would fix that. “I can handle it.”

“I thought so. If we turn up anything solid on Pat, then we’ll regroup and review. How does that strike you?”

He nodded. “Good,” he said. “Sounds good.”

I said, “The word for this week is discreet. Until and unless we come up with solid evidence, I’m not going to spit on Pat Spain’s body by calling him a murderer to the people who loved him, and I’m not going to watch you do it either. If you let any of them twig that he’s being treated as a suspect, we’re done. Do I make myself clear?”

“Yeah. Crystal.”

In the interview room, the pen was still down on the scribbled statement sheet and Conor was sagging over them, the heels of his hands pressed into his eyes. I said, “We all need sleep. We’ll hand him over for processing, get the report typed up, leave instructions for the floaters, and then we’ll go home and crash for a few hours. We’ll meet back here at noon. Now let’s go see what he’s got for us.”

I scooped my jumpers off the chair and bent to stuff them back into the holdall, but Richie stopped me. “Thanks,” he said.

He was holding out his hand and looking me straight in the face, steady green eyes. When we shook, the strength in his grip took me by surprise.

“No thanks needed,” I said. “It’s what partners do.”

The word hung in the air between us, bright and fluttering as a lit match. Richie nodded. “Sound,” he said.

I gave him a quick clap on the shoulder and went back to packing up. “Come on. I don’t know about you, but I’m dying for some kip.”

We threw our stuff into our holdalls, binned the litter of paper cups and coffee stirrers, switched off the lights and closed the observation-room door. Conor hadn’t moved. At the end of the corridor the window was still bleary with that tired city dawn, but this time the chill didn’t touch me. Maybe it was all that youthful energy beside me: the victory fizz was back in my veins and I felt wide awake again, straight-backed and strong and rock-solid, ready for whatever came next.