achs and Sellitto ascended the stairs slowly. The air in the dim stairwell smelled of pine cleanser and oil furnace heat.

"How'd he get in?" Sachs mused.

"This guy's a ghost. He gets in however he fucking wants to."

She looked up the stairwell. They paused outside the door. A nameplate said, Richter/Dobbs.!!!It won't be pretty...

"Let's do it."

Sachs opened the door and walked into Lucy Richter's apartment.

Where they were met by a muscular young woman in sweats, hair pinned up. She turned away from the uniformed officer she'd been talking to. Her face darkened as she glanced at Sachs and Sellitto and noticed the gold badges around their necks.

"You're in charge?" asked Lucy Richter angrily, stepping forward, right in Lon Sellitto's face.

"I'm one of the detectives on the case." He identified himself. Sachs did too.

Lucy Richter put her hands on her hips. "What the hell do you people think you're doing?" the soldier barked. "You know there's some psycho leaving these goddamn clocks when he kills people. And you don't tell anybody? I didn't survive all these months of combat in the goddamn desert just to come home and get killed by some motherfucker because you don't bother to share that information with the public."

It took some time to calm her down.

"Ma'am," Sachs explained, "his M.O. isn't that he's delivering these clocks ahead of time to let people know he's on his way. He was here. In your apartment. You were lucky."

Lucy Richter was indeed fortunate.

About a half hour ago a passerby happened to see a man climb onto her fire escape and head for the roof. He'd called 911 to report it. The Watchmaker had apparently glanced down, realized he'd been spotted and fled.

A search of the neighborhood could find no trace of him and no witnesses had seen anyone matching the Watchmaker's image on the computer composite.

Sachs glanced toward Sellitto, who said, "We're very sorry for the incident, Ms. Richter."

"Sorry," she scoffed. "You need to go public with it."

The detectives glanced at each other. Sellitto nodded. "We will. I'll have Public Affairs make an announcement on the local news."

Sachs said, "I'd like to search your apartment for evidence he might've left. And ask you a few questions about what happened."

"In a minute. I have to make some calls. My family'll hear about this on the news. I don't want them to worry."

"This is pretty important," Sellitto said.

The soldier opened her cell phone. In a firm voice she added, "Like I said, in a minute."

"Rhyme, you there?"

"Go ahead, Sachs." The criminalist was in his laboratory, connected to Sachs via radio. He recalled that in the next month or so they'd planned to try a high-definition video camera mounted to her head or shoulder, broadcasting to Rhyme's lab, which would let him see everything that she saw. They'd joked and called it a James Bond toy. He felt a pang that it would not be Sachs inaugurating this device with him.

Then he forced the sentiment away. What he often told those working for him he now told himself: There's a perp out there; nothing matters but catching him and you can't do that if you're not concentrating 100 percent.

"We showed Lucy the composite of the Watchmaker. She didn't recognize him."

"How'd he get inside today?"

"Not sure. If he's sticking to his M.O. he picked the front door lock. But then I think he went up to the roof and climbed down the fire escape to the vic's window. He got inside, left the clock and was waiting for her. But for some reason he climbed back outside. That's when the wit outside saw him and the Watchmaker booked on out of here. Went back up the fire escape."

"Where was he inside her apartment?"

"He left the clock in the bathroom. The fire escape is off the master bedroom so he was in there too." She paused. Then came on a moment later. "They've been canvassing for witnesses but nobody saw him or his car. Maybe he and his partner are on foot since we've got his SUV." A half dozen different subway lines serve Greenwich Village and they could easily have escaped via any of them.

"I don't think so." Rhyme explained that he felt the Watchmaker and his assistant would prefer wheels. The choice of using vehicles or not when committing a crime is a consistent pattern in a criminal's M.O. It rarely changes.

Sachs searched the bedroom, the fire escape, the bathroom and the routes he would've taken to get to those places. She checked the roof too. It had not been recently tarred, she reported.

"Nothing, Rhyme. It's like he's wearing a Tyvek suit of his own. He's just not leaving anything behind."

Edmond Locard, the famed French criminalist, developed what he called the exchange principle, which stated that whenever a physical crime occurs, there is some transfer of evidence between the criminal and the location. He leaves something of himself at the scene and he takes some of the scene with him when he departs. The principle is deceptively optimistic, though, because sometimes the trace is so minuscule it's missed and sometimes it's easily located but provides no helpful leads for investigators. Still Locard's principle holds that there would be some transfer of materials.

Rhyme often wondered, though, if there existed the rare criminal who was as smart as, or smarter than, Rhyme himself and if such a person could learn enough about forensic science to commit a crime and yet flaunt Locard's principle — leave behind no evidence and pick up none himself. Was the Watchmaker such a person?

"Think, Sachs... There's got to be more. Something we're missing. What does the vic say?"

"She's pretty shaken up. Not really concentrating."

After a pause Rhyme said, "I'm sending down our secret weapon."

Kathryn Dance sat across from Lucy Richter in the living room of her apartment.

The soldier was beneath a Jimi Hendrix poster and a wedding photo of Lucy and her husband, a round-faced, cheerful man in a dress military uniform.

Dance noted the woman was pretty calm, considering the circumstances, though, as Amelia Sachs had said, something was clearly troubling her. Dance had the impression that it was partly something other than the attack. She didn't exhibit the post-traumatic stress reactions of a near miss; she was troubled in a more fundamental way.

"If you don't mind, could you go through the details again?"

"If it'll help catch that son of a bitch, anything." Lucy explained that she'd gone to the gym to work out that morning. When she returned she found the clock.

"I was upset. The ticking..." Her face now revealed a subtle fear reaction. Fight-or-flight. At Dance's prompting she explained about the bombs overseas. "I guessed it was a present or something but it kind of freaked me out. Then I felt a breeze and went to look. I found the bedroom window open. That's when the police showed up."

"Nothing else unusual?"

"No. Not that I can remember."

Danced asked her a number of other questions. Lucy Richter didn't know Theodore Adams or Joanne Harper. She couldn't think of anyone who'd want to hurt her. She'd been trying to recall something else that could help the police but was drawing a blank.

The woman was outwardly brave ("that son of a bitch") but Dance believed that something in Lucy's mind was preventing her, subconsciously, from focusing on what had just happened. The classic defensive crossing of her arms and legs was a sign, indicating not deception but a barrier against whatever was threatening her.

The agent needed a different approach. She put her notebook down.

"What are you doing in town?" she asked conversationally.

Lucy explained that she was here on leave from her duty in the Middle East. Normally she'd have met her husband, Bob, in Germany, where they had friends, but she was getting a commendation on Thursday.

"Oh, part of that parade, supporting the troops?"

"Right afterward."

"Congratulations."

Her smile fluttered. Dance noticed the minuscule reaction.

And she noted one in herself, as well; Kathryn Dance's husband had been recognized for bravery under fire by the Bureau four days before he'd died. But that was a crackle of static that Dance immediately tuned out.

Shaking her head, the agent continued. "You come back to the States and look what happens — you run into this guy. That's pretty shitty. Especially after being overseas."

"It's not that bad over there. Sounds worse on the news."

"Still... But it looks like you're coping pretty well."

Her body was telling a very different story.

"Oh, yeah. You do what you have to. No big deal." Her fingers were-entwined.

"What do you do there?"

"I manage fuelers. Basically it's running supply trucks."

"Important job."

A shrug. "I guess."

"Good to be here on leave, I'll bet."

"You ever in the service?"

"No," Dance answered.

"Well, in the army, remember rule number one: Never pass up R and R. Even if it's just drinking punch with the brass and collecting a wall decoration."

Dance kept drawing her out. "How many other soldiers'll be at the ceremony?"

"Eighteen."

Lucy wasn't comfortable at all. Dance wondered if her underlying uneasiness was because she might have to say a few words in front of the crowd. Public speaking was higher on the fear scale than skydiving. "And how big's the event going to be?"

"I don't know. A hundred. Maybe two."

"Is your family going?"

"Oh, yeah. Everybody. We're going to have a reception here afterward."

"As my daughter says," Dance offered, "parties rock. What's on the menu?"

"Forgeddabout it," Lucy joked. "We're in the Village. It'll be Italian. Baked ziti, scampi, sausage. My mother and aunt're cooking. I'm making dessert."

"My downfall," Dance said. "Sweets... I'm getting hungry." Then she said, "Sorry, I got distracted." Leaving the notebook closed, she looked into the woman's eyes. "Back to your visitor. You were saying, you made your tea. Running the bath. You feel a breeze. You go into the bedroom. The window's open. What was I asking? Oh, was there anything else you saw that was out of the ordinary?"

"Not really." She said this quickly, as before, but then she squinted. "Wait. You know... there was one thing."

"Really?"

Dance had done what's known as "flooding." She'd decided that it wasn't only the Watchmaker that was bothering Lucy but rather her duty overseas, as well as the upcoming awards ceremony, for some reason. Dance had gone back to the topics and kept bombarding her with questions, in hopes of numbing her and letting the other memories break through.

Lucy rose and walked to the bedroom. Saying nothing, Dance followed her. Amelia Sachs joined them.

The soldier looked around the room.

Careful, Dance told herself. Lucy was onto something. Dance kept silent. Too many interviewers ruin a session by pouncing. The rule with vague memories is that you can let them surface but you can rarely reel them in.!!!Watching and listening are the two most important parts of the interview. Talking comes last.

"There was something that bothered me, something other than the window being open... Oh, you know what? I've got it. When I walked to the bedroom earlier, to see about the ticking, something was different — I couldn't see the dresser."

"Why was that unusual?"

"Because when I left to go to the health club I glanced at it to see if my sunglasses were there. They were and I picked them up. But then when I looked into the room later, when I heard the ticking, I couldn't see the dresser — because the closet door was partly open."

Dance said, "So after the man left the clock he was probably hiding in the closet or behind the door."

"Makes sense," Lucy said.

Dance turned to Sachs, who nodded with a smile and said, "Good. I better get to work." And she pulled open the closet door with her latex-gloved hand.

A second time they'd failed.

Duncan was driving even more carefully, meticulously, than he usually did.

He was silent and completely calm. Which bothered Vincent even more. If Duncan slammed down his fist and screamed, like his stepfather, Vincent would have felt better. ("You did what?" the man had raged, referring to the rape of Sally Anne. "You fat pervert!") He was worried that Duncan had had enough and was going to give up the whole thing.

Vincent didn't want his friend to go away.

Duncan merely drove slowly, stayed in his lane, didn't speed, didn't try to beat yellow lights.

And didn't say a word for a long time.

Finally he explained to Vincent what had happened: As he'd started to climb to the roof — planning to get into the building, knock on Lucy's door and get her to hang up the phone, he'd glanced down and seen a man in the alley, staring at him, pulling his cell phone from his pocket, shouting for Duncan to stop. The killer had hurried to the roof, run west several buildings then rapelled into the alley. He'd then sprinted to the Buick.

Duncan was driving meticulously, yes, but without any obvious destination. At first Vincent wondered if this was to lose the police but there didn't seem to be any risk of pursuit. Then he decided that Duncan was on automatic pilot, driving in large circles.

Like the hands of a clock.

Once again the shock of a narrow escape faded and Vincent felt the hunger growing again, hurting his jaw, hurting his head, hurting his groin.!!!If we don't eat, we die.

He wanted to be back in Michigan, hanging out with his sister, having dinner with her, watching TV. But his sister wasn't here, she was miles and miles away, maybe thinking of him right now — but that didn't give him any comfort... The hunger was too intense. Nothing was working out! He felt like screaming. Vincent had better luck cruising strip malls in New Jersey or waiting for a college coed or receptionist jogging through a deserted park. What was the point of —

In his quiet voice Duncan said, "I'm sorry."

"You...?"

"I'm sorry."

Vincent was disarmed. His anger diminished and he wasn't sure what to say.

"You've been helping me, working hard. And look what's happened. I've let you down."

Here was Vincent's mother, explaining to him, when he was ten, that she'd let him down with Gus, then with her second husband, then with Bart, then with Rachel the experiment, then with her third husband.

And every time, young Vincent had said just what he said now. "It's okay."

"No, it's not... I talk about the great scheme of things. But that doesn't minimize our disappointments. I owe you. And I'll make it up to you."

Which is something his mother never said, much less did, leaving Vincent to find what comfort he could in food, TV shows, spying on girls and having his heart-to-hearts.

No, it was clear that his friend, Duncan, meant what he was saying. He was genuinely remorseful that Vincent hadn't been able to have Lucy. Vincent still felt the urge to cry but now for a different reason. Not from the hunger, not from frustration. He felt filled with an odd sensation. People hardly ever said nice things to him like this. People hardly ever worried about him.

"Look," Duncan said, "the one I'm going to do next. You're not going to want her."

"Is she ugly?"

"Not really. It's just the way she's going to die... I'm going to burn her."

"Oh."

"In the book, remember the alcohol torture?"

"Not really."

The pictures in the book were of men being tortured; they hadn't interested Vincent.

"You pour alcohol on the lower half of someone's body and set fire to it. You can put out an alcohol fire quickly if they confess. Of course, I'm not going to be putting it out."

True, Vincent agreed, he wouldn't want her after that.

"But I have another idea."

Duncan then explained what he had in mind, Vincent's spirits improving with every word. Duncan asked, "Don't you think it'll work out for everybody?"

Well, not quite everybody, thought Clever Vincent, who was back and in a pretty good mood, all things considered.

Sitting in front of the evidence charts, Rhyme heard Sachs come back on the line.

"Okay, Rhyme. We've found he was hiding in the closet."

"Which one?"

"In Lucy's bedroom."

Rhyme closed his eyes. "Describe it to me."

Sachs gave him the whole scene — the hallway leading to the bedroom, the layout of the bedroom itself then the furniture, pictures on the wall, the Watchmaker's entrance and exit route and other details. Everything was described in precise, objective detail. Her training and experience shone as sharply as her red hair. If she left the force he wondered how long it would take another cop to walk the grid as well as she did.

Forever, he thought cynically.

Anger flared for a moment. Then he forced the emotion away and concentrated again on her words.

Sachs described the closet. "Six feet four inches wide. Filled with clothes. Men's on the left, women's on the right, half and half. Shoes on the floor. Fourteen pair. Four men's, ten women's."

A typical ratio, Rhyme reflected, for a married couple, thinking of his own closet from years ago. "When he was hiding, was he lying on the floor?"

"No. Too many boxes."

He heard her ask a question. Then she came back on the line. "The clothes're ordered now but he must've moved them. I can see some boxes moved on the floor and a few bits of that roofing tar we found earlier."

"What were the clothes he was hiding between?"

"A suit. And Lucy's army uniform."

"Good." Certain garments, like uniforms, are particularly good at collecting evidence, thanks to their prominent epaulettes, buttons and decorations. "Was he against the front or back?"

"Front."

"Perfect. Go over every button, medal, bar, decoration."

"Okay. Give me a few minutes."

Then silence.

His impatience, laced with anger, was back. He stared at the whiteboards.

Finally she said, "I found two hairs and some fibers."

He was about to tell her to check the hairs against samples in the apartment. But of course he didn't need to do this. "I compared the hairs to hers. They don't match." He began to tell her to find a sample of the woman's husband's hair when Sachs said, "But I found her husband's brush. I'm ninety-nine percent sure they're his."

Good, Sachs. Good.

"But the fibers... they don't seem to match anything else here." Sachs paused. "They look like wool, light-colored. Maybe a sweater... but they were caught on a pocket button at about shoulder level for a man of the Watchmaker's height. Could be a shearling collar."

A reasonable deduction, though they'd have to examine the fibers more carefully in the lab.

After a few minutes she said, "That's about it, Rhyme. Not much but it's something."

"Okay, bring everything in. We'll go over it here." He disconnected the line.

Thom wrote down the information Sachs gave them. After the aide left the room Lincoln Rhyme stared again at the charts. He wondered if the notes he was looking at weren't simply clues in a homicide case, but evidence of a different sort of murder: the corpse of the last crime scene he and Amelia Sachs would ever work together.

Lon Sellitto was gone and, inside Lucy Richter's apartment, Sachs was just finishing packing up the evidence. She turned to Kathryn Dance and thanked her.

"Hope it's helpful."

"That's the thing about crime scene work. Only a couple of fibers, but they could be enough for a conviction. We'll just have to see." Sachs added, "I'm heading back to Rhyme's. Listen, I don't know if you'd be willing but could you do some canvassing in the neighborhood? You've sure got the touch when it comes to wits."

"You bet."

Sachs gave her some printouts with the Watchmaker's composite picture and left, to head back to Rhyme's.

Dance nodded at Lucy Richter. "You're doing okay?"

"Fine," the solider replied and offered a stoic smile. She walked into the kitchen and put the kettle on the stove. "You want some tea? Or coffee?"

"No. I'm going to be outside looking for witnesses."

Lucy was staring down at the floor, a good semaphore signal to a kinesics expert. Dance said nothing.

The soldier said, "You said you were from California. You going back soon?"

"Tomorrow, probably."

"Just wondering if you'd have time for coffee or something." Lucy played with a potholder. On it were the words 4th Infantry Division. Steadfast and Loyal.

"Sure. We'll work it out." Dance found a card in her purse and wrote her hotel name on it, then circled her mobile on the front.

Lucy took it.

"Call me," Dance said.

"I will."

"Everything okay?"

"Oh, sure. Just fine."

Dance shook the woman's hand, then left the apartment, reminding herself of an important rule in kinesic analysis: Sometimes you don't need to uncover the truth behind every deception you're told.