The call she’d taken in the cab was from him, once again asking if she’d help them in the case. “I know you’ve got a flight, I know you’ve got to get home, but . . .”

He explained that they’d discovered a possible source for the clocks left at the Watchmaker’s crime scenes and wanted her to interview the man who might’ve sold them. There was a possibility, though slight, that he had some connection with the Watchmaker and they wanted her opinion about him.

Dance had debated only a brief moment before agreeing. She’d regretted her abrupt departure from Lincoln Rhyme’s town house earlier; Kathryn Dance hated leaving a case unfinished, even if it wasn’t hers. She’d had the cab turn around and return to Rhyme’s, where Lon Sellitto was waiting for her.

Now, in the detective’s car, Dance asked, “It was your idea to call me, wasn’t it?”

“How’s that?” Sellitto asked.

“Not Lincoln’s. He’s not sure what to make of me.”

His one-second pause was a flashing sign. Sellitto said, “You did a good job with that witness, Cobb.”

Dance smiled. “I know I did. But he’s not sure what to make of me.”

Another pause. “He likes his evidence.”

“Everybody has their weaknesses.”

The detective laughed. He hit the siren button and they sped through a red light.

As he drove, Dance glanced at him, watched his hands and eyes, listened to his voice. She assessed: He’s truly obsessed with getting the Watchmaker, and the other cases undoubtedly sitting on his desk now are as insubstantial as steam. And, as she’d observed when he was in her class yesterday, he was dogged and savvy, with no problem taking as much time as he needed to understand a problem or to get an interrogation technique right; if anybody grew impatient with him, well, that was their problem.

His energy’s nervous but very different from that of Amelia Sachs, who has harm issues. He grumbles out of habit but he’s essentially a very content man.

This was something Dance did automically, the analysis. A gesture, a glance, an offhand statement became to her another piece of that miraculous puzzle that was a human being. She was usually able to shut it off when she wished—it’s no fun to be out for a Pinot Grigio or Anchor Steam beer and finding yourself analyzing your drinking buddies (and it’s a lot less fun for them). But sometimes the thoughts just flowed; this habit went with the territory of being Kathryn Dance.

The people addict . . .

“You have a family?” he asked.

“Two children, yes.”

“And what’s your husband do?”

“I’m a widow.” Dance’s job was recognizing the effect of different tones of voice, and she now delivered these words in a particular way, both offhand and grave, which he would take to mean “I don’t want to talk about it.” A woman might grip her arm in sympathy; Sellitto did what most of his sex would: muttered a genuine but awkward “sorry” and moved on. He began talking about the evidence they’d found in the case and the leads—which were primarily nonleads. He was funny and gruff.