“This young one,” O’Kelly said. He was clicking the top of his pen with his thumb, watching it like it was fascinating stuff. “Quigley tried to tell me ye were all having some mad three-way—said he was concerned because the squad should be upholding morals, all that altar-boy shite. What’s the real story?”

O’Kelly has always been good to me. “She’s my sister,” I said.

That got his attention. “Holy God. I’d say Curran is missing a few teeth now, is he?”

“He didn’t know.”

“That’s no excuse. Dirty little whoremaster.”

I said, “Sir, I’d like to keep my sister out of this, if possible. She’s not well.”

“That’s what Quigley said, all right.” Only presumably not in those words. “No need to bring her into it. IA might want to talk to her, but I’ll tell them there’s nothing she can add. You make sure she doesn’t go chatting to some media bastard, and she’ll be grand.”

“Thank you, sir.”

O’Kelly nodded. “This,” he said, flicking the envelope with his pen. “Can you swear you never saw it till today?”

I said, “I swear, sir. I didn’t know it existed till Quigley waved it in my face.”

“When did Curran pick it up?”

“Thursday morning.”

“Thursday morning,” O’Kelly repeated. Something ominous was building in his voice. “So he kept it to himself for the bones of two days. The two of ye are spending every waking moment together, you’re talking about nothing only this case—or at least I hope you are—and Curran’s got the answer in the pocket of his shiny tracksuit the whole time. Tell me, Detective: how the sweet living fuck did you miss that?”

“I was focused on the case. I did notice—”

O’Kelly exploded. “Sweet Jesus! What does this yoke look like to you? Chopped liver? This is the fucking case. And it’s not some piece-of-shite druggie case where nobody cares if you take your eye off the ball. There are murdered kids here. You didn’t think this might be a good time to act like a bloody detective and keep an eye on what’s going on around you?”

I said, “I knew something was on Curran’s mind, sir. I didn’t miss that. But I thought it was because we weren’t on the same page. I thought Brennan was our man, and looking anywhere else was a waste of time; Curran thought—said he thought—that Patrick Spain was a better suspect and we should spend more time on him. I thought that was all it was.”

O’Kelly took a breath to keep bollocking me, but his heart wasn’t in it. “Either Curran deserves an Oscar,” he said, but the heat had gone out of his voice, “or you deserve a good kicking.” He rubbed his eyes with thumb and finger. “Where is the little prick, anyway?”

“I sent him home. I wasn’t about to let him touch anything else.”

“Too bloody right. Get onto him, tell him to report to me first thing in the morning. If he survives that, I’ll find him a nice desk where he can file paperwork till IA’s done with him.”