And none at midmorning… nor late afternoon.

They were no longer able to enlist the numbers-crunching forces from the police academy, to review the massive amounts of evidence from the scene on Twenty-sixth Street, though the head of the Crime Scene Unit agreed to dedicate some extra technicians. Marko had taken the bulk of the collected materials from Rhyme’s to the labs in Queens.

But the hours rolled by and all the updates included variations on: “There’s just too much evidence.”

Clues had never failed Rhyme so badly as in this case. He’d built his whole professional life on finding the truth because of physical evidence. In fact, he was contemptuous of other forms of investigation. Witnesses lied, motives were fishy, vivid memories were completely wrong.

Locard’s Principle…

At 6:00 p.m. Mel Cooper, Sachs and Rhyme were still laboring away, doing what they could with the several hundred samples that remained here in his parlor but not making any headway.

There’s just too much…

Rhyme reached for one of the hair sample bags. “Let’s keep going with follicles and CODIS.” The consolidated database that contained DNA samples from tens of thousands of perpetrators.

But he set it down and wheeled back from a work table. His expression must have been particularly troubled. Sachs, too, stopped her analysis of a sheet of paper, walked behind him and massaged his shoulders, which were tense as stone.

It felt nice…

But didn’t take away the frustration.

Rhyme gazed at the largely useless evidence, trying desperately to think of a different approach. It was clear that the classic textbook procedure for running a case forensically wasn’t going to work.

What else could he—?

Textbook.

“Sachs!”

“What?” She stopped the massage and walked around in front of him.

“Textbook. Think about what I’ve been saying for the past couple of days. My textbook.”

The evidence chart reads like the table of contents in my goddamn book….

Sachs was nodding. “It’s like everything he knows about evidence and crime scenes, he learned from your book.”

He pointed to the chart. “There’s a separate chapter for each of those categories of evidence collection and analysis. And I wrote sections about contamination, having too much evidence, and arson as a means to obliterate it. Somebody who bought or borrowed my text is the perp.”

“How many copies did you sell?” Cooper asked. He knew the book well; he was one of the dedicatees.

“About twenty thousand.”

“Not very helpful then.”

Rhyme considered this. “I’m not so sure. People aren’t going to curl up with it on cold winter nights like they would with Harry Potter or one of those vampire books now, are they? The vast bulk of sales would be to law enforcement. But let’s put them aside for the time being—it’s too obvious, too traceable. Somebody with a forensic specialty’d be the first people we’d look at.”

“We’ll drop everything and get in touch with publishers and retailers.”

“How do we factor out law enforcement sales?” Cooper asked.