A clock. An old-fashioned one, with those funny numbers-Roman numerals-and a moon face on the front. Looked expensive. He glanced at his watch and saw the clock was working; the time was accurate. Who'd leave a nice thing like that here? Well, all right, I got myself a present.

As he stepped forward to pick it up, though, his legs went out from under him and he had a moment of pure panic thinking he'd tumble into the river. But he went straight down, landing on the patch of ice he hadn't seen, and slid no further.

Wincing in pain, gasping, he pulled himself to his feet. The man glanced down and saw that this wasn't normal ice. It was reddish brown.

"Oh, Christ," he whispered as he stared at the large patch of blood, which had pooled near the clock and frozen slick. He leaned forward and his shock deepened when he realized how the blood had gotten there. He saw what looked like bloody fingernail marks on the wooden decking of the pier, as if someone with slashed fingers or wrists had been holding on to keep from falling into the churning waters of the river.

He crept to the edge and looked down. No one was floating in the choppy water. He wasn't surprised; if what he imagined was true, the frozen blood meant the poor bastard had been here a while ago and, if he hadn't been saved, his body'd be halfway to Liberty Island by now.

Fumbling for his cell phone, he backed away and pulled his glove off with his teeth. A final glance at the clock, then he hurried back to the shed, calling the police with a stubby, quaking finger.

Before and After.

The city was different now, after that morning in September, after the explosions, the huge tails of smoke, the buildings that disappeared.

You couldn't deny it. You could talk about the resilience, the mettle, the get-back-to-work attitude of New Yorkers, and that was true. But people still paused when planes made that final approach to LaGuardia and seemed a bit lower than normal. You crossed the street, wide, around an abandoned shopping bag. You weren't surprised to see soldiers or police dressed in dark uniforms carrying black, military-style machine guns.

The Thanksgiving Day parade had come and gone without incident and now Christmas was in full swing, crowds everywhere. But floating atop the festivities, like a reflection in a department store's holiday window, was the persistent image of the towers that no long were, the people no longer with us. And, of course, the big question: What would happen next?

Lincoln Rhyme had his own Before and After and he understood this concept very well. There was a time he could walk and function and then came the time when he could not. One moment he was as healthy as everyone else, searching a crime scene, and a minute later a beam had snapped his neck and left him a C-4 quadriplegic, almost completely paralyzed from the shoulders down.

Before and After…

There are moments that change you forever.

And yet, Lincoln Rhyme believed, if you make too grave an icon of them, then the events become more potent. And the bad guys win.

Now, early on a cold Tuesday morning, these were Rhyme's thoughts as he listened to a National Public Radio announcer, in her unshakable FM voice, report about a parade planned for the day after tomorrow, followed by some ceremonies and meetings of government officials, all of which logically should have been held in the nation's capital. But the up-with-New-York attitude had prevailed and spectators, as well as protesters, would be present in force and clogging the streets, making the life of security-sensitive police around Wall Street far more difficult. As with politics, so with sports: Play-offs that should occur in New Jersey were now scheduled for Madison Square Garden-as a display, for some reason, of patriotism. Rhyme wondered cynically if next year's Boston Marathon would be held in New York City.

Before and After…

Rhyme had come to believe that he himself really wasn't much different in the After. His physical condition, his skyline, you could say, had changed. But he was essentially the same person as in the Before: a cop and a scientist who was impatient, temperamental (okay, sometimes obnoxious), relentless and intolerant of incompetence and laziness. He didn't play the gimp card, didn't whine, didn't make an issue of his condition (though good luck to any building owners who didn't meet the Americans with Disabilities Act requirements for door width and ramps when he was at a crime scene in their buildings).

As he listened to the report now, the fact that certain people in the city seemed to be giving in to self-pity irritated him. "I'm going to write a letter," he announced to Thom.

The slim young aide, in dark slacks, white shirt and thick sweater (Rhyme's Central Park West town house suffered from a bad heating system and ancient insulation), glanced up from where he was overdecorating for Christmas. Rhyme enjoyed the irony of his placing a miniature evergreen tree on a table below which a present, though an unwrapped one, already waited: a box of adult disposable diapers.

"Letter?"

He explained his theory that it was more patriotic to go about business as usual. "I'm going to give ' em hell. The Times , I think."

"Why don't you?" asked the aide, whose profession was known as "caregiver" (though Thom said that, being in the employ of Lincoln Rhyme, his job description was really "saint").

"I'm going to," Rhyme said adamantly.

"Good for you…though, one thing?"

Rhyme lifted an eyebrow. The criminalist could-and did-get great expression out of his extant body parts: shoulders, face and head.

"Most of the people who say they're going to write a letter don't. People who do write letters just go ahead and write them. They don't announce it. Ever notice that?"

"Thank you for the brilliant insight into psychology, Thom. You know that nothing's going to stop me now."

"Good," repeated the aide.

Using the touchpad controller, the criminalist drove his red Storm Arrow wheelchair closer to one of the half dozen large, flat-screen monitors in the room.

"Command," he said into the voice-recognition system, via a microphone attached to the chair. "Word processor."

WordPerfect dutifully opened on the screen.

"Command, type. 'Dear sirs.' Command, colon. Command, paragraph. Command, type, 'It has come to my attention-'"

The doorbell rang and Thom went to see who the visitor was.

Rhyme closed his eyes and was composing his rant to the world when a voice intruded. "Hey, Linc. Merry Christmas."

"Uhm, ditto," Rhyme grumbled to paunchy, disheveled Lon Sellitto, walking through the doorway. The big detective had to maneuver carefully; the room had been a quaint parlor in the Victorian era but now was chock-ablock with forensic science gear: optical microscopes, an electron microscope, a gas chromatograph, laboratory beakers and racks, pipettes, petri dishes, centrifuges, chemicals, books and magazines, computers-and thick wires, which ran everywhere. (When Rhyme began doing forensic consulting out of his town house, the power-hungry equipment frequently would blow circuit breakers. The juice running into the place probably equaled the combined usage by everyone else on the block.)

"Command, volume, level three." The environmental control unit obediently turned down NPR.

"Not in the spirit of the season, are we?" the detective asked.

Rhyme didn't answer. He looked back at the monitor.

"Hey, Jackson." Sellitto bent down and petted a small, longhaired dog curled up in an NYPD evidence box. He was temporarily living here; his former owner, Thom's elderly aunt, had passed away recently in Westport, Connecticut, after a long illness. Among the young man's inheritances was Jackson, a Havanese. The breed, related to the bichon frise, originated in Cuba. Jackson was staying here until Thom could find a good home for him.