taxicab pulled up in front of the Metropolitan Museum of Art, on Fifth Avenue. The huge building was decorated for Christmas, dolled up in the tasteful Victorian regalia that you'd expect on the Upper East Side. Subdued festive.

Out of this cab climbed Charles Vespasian Hale, who looked around carefully on the remote chance that the police were following him. It would have been exceedingly unlikely that he'd be under surveillance. Still, Hale took his time, looked everywhere for anyone showing him the least attention. He saw nothing troubling.

He leaned down to the open taxi window and paid the driver — tendering the cash in gloved hands — and, hooking a black canvas bag over his shoulder, he climbed the stairs into the large cathedral-like lobby, which echoed with the sound of voices, most of them young; the place was lousy with kids freed from school. Evergreens and gold and ornaments and tulle were everywhere. Bach two-part inventions plucked away cheerily on a recorded harpsichord, echoing in the cavernous entryway.!!!'Tis the season...

Hale left the black bag at the coat check, though he kept his coat and hat. The clerk looked inside the bag, noted the four art books, then zipped it back up and told Hale to have a nice day. He took the claim check and paid admission. He nodded a smile at the guards at the entrance and walked past them into the museum itself.

"The Delphic Mechanism?" Rhyme was talking to the director of the Metropolitan Museum of Art via speakerphone. "It's still on display there?"

"Yes, Detective," the man replied uncertainly. "We've had it here for two weeks. It's part of a multicity tour —"

"Fine, fine, fine. Is it guarded?"

"Yes, of course. I —"

"There's a possibility that a thief's trying to steal it."

"Steal it? Are you sure? It's a one-of-a-kind objet. Whoever took possession could never show it in public."

"He doesn't intend to sell it," Rhyme said. "I think he wants it for himself."

The criminalist explained: The package stolen from the delivery service in the building on Thirty-second Street was from a wealthy patron of the arts and was destined for the Metropolitan Museum. It contained a large portfolio of some antiques being offered to the museum's furniture collection.

The Metropolitan Museum? Rhyme had wondered. He'd then recalled the museum programs found in the church. He'd asked Vincent Reynolds and the clock dealer, Victor Hallerstein, if Duncan had mentioned anything about the Met. He had, apparently — spending considerable time there — and he'd expressed particular interest in the Delphic Mechanism.

Rhyme now told the director, "We think he may have stolen the package to smuggle something into the museum. Maybe tools, maybe software to disable alarms. We don't know. I can't figure it out at this point. But I think we have to be cautious."

"My God... All right. What do we do?"

Rhyme looked up at Cooper, who typed on his keyboard and gave a thumbs-up. Into the microphone the criminalist said, "We've just emailed you his picture. Could you print it out and get a copy to all the employees, the security surveillance room and the coat check? See if they recognize him."

"I'll do it right now. Can you hold for a few minutes?"

"Sure."

Soon the director came on the line. "Detective Rhyme?" His voice was breathless. "He's here! He checked a bag about ten minutes ago. The clerk recognized the picture."

"The bag's still there?"

"Yes. He hasn't left."

Rhyme nodded at Sellitto, who picked up the phone and called Bo Haumann at ESU, whose teams were on their way to the museum, and told him this latest news.

"The guard at the Mechanism," Rhyme asked, "is he armed?"

"No. Do you think the thief is? We don't have metal detectors at the entrance. He could've brought a gun in."

"It's possible." Rhyme looked at Sellitto with a lifted eyebrow.

The detective asked, "Move a team in slow? Undercover?"

"He checked a bag... and he knows clocks." He asked the museum director, "Did anybody look in the bag?"

"I'll check. Hold on." A moment later he came back. "Books. He has art books inside. But the coat-check clerk didn't examine them."

"Bomb for diversion?" Sellitto asked.

"Could be. Maybe it's only smoke but even then people'll panic. Could be fatalities either way."

Haumann called in on his radio. His crackling voice: "Okay, we've got teams approaching all the entrances, public and service."

Rhyme asked Dance, "You're convinced he's willing to take lives."

"Yes."

He was considering the man's astonishing plot-making skills. Was there some other deadly plan he'd put into play if he realized he was about to be arrested at the museum? Rhyme made a decision. "Evacuate."

Sellitto asked, "The entire museum?"

"I think we have to. First priority — save lives. Clear the coatroom and front lobby and then move everybody else out. Have Haumann's men check out everybody who leaves. Make sure the teams have his picture."

The museum director had heard. "You think that's necessary?"

"Yes. Do it now."

"Okay, but I just don't see how anyone could steal it," the director said. "The Mechanism's behind inch-thick bullet-proof glass. And the case can't be opened until the day the exhibit closes, next Tuesday."

"What do you mean?" Rhyme asked.

"It's in one of our special display cases."

"But why won't it open until Tuesday?"

"Because the case has a computerized time lock, with a satellite link to some government clock. They tell me nobody can break into it. We put the most valuable exhibits in there."

The man continued speaking but Rhyme looked away. Something was nagging him. Then he recalled, "That arson earlier, the one that Fred Dellray wanted us to help out on. Where was it again?"

Sachs frowned. "A government office. The Institute of Standards and Technology or something like that. Why?"

"Look it up, Mel."

The tech went online. Reading from the website, he said, "NIST is the new name for the National Bureau of Standards and —"

"Bureau of Standards?" Rhyme interrupted. "They maintain the country's atomic clock... Is that what he's up to? The time lock at the Met has an uplink to the NIST. Somehow he's going to change the time, convince the lock that it's next Tuesday. The vault'll open automatically."

"Can he do that?" Dance asked.

"I don't know. But if it's possible, he'll find a way. The fire at NIST was to cover up the break-in, I'll bet... " Then Rhyme stopped talking, as the full implications of the Watchmaker's plan became clear. "Oh, no..."

"What?"

Rhyme was thinking about Kathryn Dance's observation: That to the Watchmaker, human life was negligible. He said, "Time everywhere in the country is governed by the U.S. atomic clock. Airlines, trains, national defense, power grids, computers... everything. Do you have any idea what's going to happen if he resets it?"

In a cheap Midtown hotel, a middle-aged man and woman sat on a small couch that smelled of mildew and old food. They were staring at a television set.

Charlotte Allerton was the stocky woman who'd pretended to be the sister of Theodore Adams, the first "victim" in the alley on Tuesday. The man beside her, Bud Allerton, her husband, was the man masquerading as the lawyer who'd secured Gerald Duncan's release from jail by promising that his client would be a spectacular witness in the crooked cop scandal.

Bud really was a lawyer, though he hadn't practiced for some years. He'd resurrected some of his old skills for the sake of Duncan's plan, which called for Bud's pretending to be a criminal attorney from the big, prestigious law firm of Reed, Prince. The assistant district attorney had bought the entire charade, not even bothering to call the firm to check up on the man. Gerald Duncan had believed, correctly, that the prosecutor would be so eager to make a name for himself on a police corruption case that he'd believe what he wanted to. Besides, who ever asks for a lawyer's ID?

The Allertons' attention was almost exclusively on the TV screen, showing local news. A program about Christmas tree safety. Yadda, yadda, yadda... For a moment Charlotte's gaze slipped to the master bedroom in the suite, where her pretty, thin daughter sat reading a book. The girl looked through the doorway at her mother and stepfather with the same dark, sullen eyes that had typified her expression in recent months.

That girl...

Frowning, Charlotte looked back to the TV screen. "Isn't it taking too long?"

Bud said nothing. His thick fingers were intertwined and he sat forward, hunched, elbows on knees. She wondered if he was praying.

A moment later the reporter whose mission was to save families from the scourge of burning Christmas trees disappeared and on the screen came the words!!!Special News Bulletin.