Cardinal headed to a series of doors past the counter and beyond the shelves of guitars. "Which room?"

"Wait a minute, now. What on earth is this about?"

"Collingwood, stay here with Mr. Troy."

The first door was a supply closet. In the second, a startled woman looked up from the piano where she was counting aloud to a metronome. In the third room, Carl Sutherland was shaping the little fingers of a ten-year-old boy around a guitar chord. He looked up sharply.

"Are you Carl Sutherland?"

"Yes?"

"Police. Would you come with us, please?"

"What do you mean? I'm in the middle of a lesson."

"Would you excuse us?" Delorme said to the boy. "We have something to discuss with Mr. Sutherland."

When the boy was gone, Cardinal shut the door. "You gave Billy LaBelle guitar lessons, didn't you?"

"Yes. I already talked to the police about-"

"And you also knew Katie Pine, didn't you?"

"Katie Pine? The girl who was murdered? Absolutely not. I saw her picture in the paper, but other than that I never saw her in my life."

"Our information is different," Delorme put in. "Our information says Katie Pine was in here two days before she disappeared."

"If she was, I didn't see her. Why are you coming to me? It's a big mall out there. Everybody in town goes through."

"Everybody in town doesn't get picked up for public indecency, Mr. Sutherland."

"Oh, God."

"Everybody in the mall doesn't get arrested for exposing himself in the back seat of a porno theater."

"Oh, God." Sutherland swayed slightly in his seat, his face utterly white. "I thought that was over and done with."

"You want to come down to the station and tell us about it? Or maybe we should ask your wife."

"You can't bully me like this. I was acquitted on that charge." Sutherland's voice was now harsh, indignant, but his face was still white. "I'm not proud of what happened. But I don't see why I have to be humiliated over it, either. A pitch-dark theater is not public. It's not public, and the judge agreed. Besides which, what went on was entirely between consenting adults and it's none of your business."

"Billy LaBelle is our business. You were one of the last people to see him alive."

"Well, what does this have to do with Billy LaBelle?"

"Why don't you tell us?" Delorme said. "You were his teacher."

"Yes, I was Billy's guitar teacher. I've already discussed all this. Billy left the store one Wednesday night- the same as every other Wednesday night- and I never saw him again. It's very sad. Billy was a really nice kid. But I didn't do anything to him. I swear I didn't."

"Are you telling us you don't know this boy?" Cardinal produced the photo of Keith London playing guitar.

"I don't. I don't know every kid that happens to play guitar."

Sutherland hadn't been phased at all by the picture. He was scared, yes, he was shaken, but the picture of Keith London did not seem any particular threat. Cardinal's certainty began to slip. He pulled out the picture of Katie Pine.

"That's the girl who was killed. I recognize her from the papers. Other than that I don't think I've ever seen her."

"She was in here two days before she disappeared. She bought a musical charm for her bracelet. You sell them out front."

"She could have got it somewhere else."

"She bought it here."

"I never saw the girl, I'm telling you. Look in the inventory, and you'll see."

"Inventory?"

"We've had computerized inventory for years, now. It'll tell you who sold the thing to her. It's not like we sell a million of them. Three or four a month, I'd say."

As they came out of the practice room, Alan Troy called, "What is it, Carl? What's going on?" But Sutherland ignored him, leading Cardinal and Delorme to a cramped office in the back. Almost buried among stacks of invoices, a computer screen glowed with columns of numbers. Sutherland sat down and typed in a couple of commands. The screen went dark, except for the cursor pulsing in the top left corner.

"You have the date?" he asked without looking at them. "The date the girl disappeared?"

"September twelfth, last year. She bought the charm two days before."

"Fine. Now, I need the item number." He consulted a printout the size of a telephone book, flipping through the double-sized pages until he found what he wanted. He typed in the number. "This should tell us how many we sold in the past year." He drummed his fingers on the desk as he waited. "Seven. Okaaay…" He typed in another command, the monthly breakdown.

"September tenth." Delorme pointed at the screen. "Two days before."

Sutherland moved the mouse and clicked. The screen filled up with a copy of the register receipt. He tapped the long fingernail of his right hand on the upper right corner. "You see that number three? That's the salesperson. One is Alan, two is me, three is Eric."

"Eric who?"

"Eric our part-timer. Eric Fraser. Mostly he helps with the stock, but busy times- lunch hours, after-school rush- he helps with the cash, too. If you look at the top left there you can see the time of the transaction: four-thirty P.M. If you look at our calendar, it's going to show you I was teaching a lesson at that time. I think you want to talk to Eric Fraser."

"Mr. Sutherland, is there anything around here that Mr. Fraser touched recently? Something nobody else touched?"

Sutherland thought for a minute. "Follow me."

Alan Troy dodged around Collingwood, finger jabbing the air, demanding to know what was going on. Sutherland cut him off. "Alan, did Eric polish the Martins yesterday?"

"I'm calling the chief of police on this. My employees do not get treated in this way. These people have to-"

"Alan, for Chrissake, just tell them. Did Eric polish the Martins yesterday?"

"The Martins?" Troy squinted first at Sutherland, then at Delorme, then at Cardinal, and back to Sutherland. "You want to know if Eric polished the Martins. Suddenly the urgent question of the moment is, did Eric Fraser polish the Martins? All right, then, yes. Eric did polish the Martins."

Cardinal asked if anyone else had touched the guitars. No. Business had been slow, Martins are expensive, no one had touched them.

Cardinal, still wearing his gloves, reached up for the guitar hanging against the wall. "He'd have to hold it at the bottom to put it back up there, right?"

Mr. Troy, his anger giving way to fascination, nodded. Cardinal held the guitar out toward Collingwood.

Collingwood, silent as ever, dusted a small amount of powder along the top of the soundboard, then blew it off. Two perfect thumbprints took shape. He pulled the Forensic card from his pocket, the thumbprints lifted from Arthur Wood's throat.

"Perfect match," Collingwood said. "Perfect match, plain as day."