Archie rode in the lead truck. Claire Hasson, a company driver, was behind the wheel. In the side mirror, Archie could see the convoy stretching back around a curve. They were on Route 68, which would connect via I295 with the Pennsylvania Turnpike. They were headed for Carlisle and the Blue Mountains. Ridiculous, in Archie's mind. But, by God, it would take one very large tidal wave to sink them up there.

Carlisle hadn't been the first choice. But they'd been unable to find commercial accommodations anywhere in Pennsylvania's mountain country. After hours of fruitless calls, Walter had pulled strings with lodge brothers who'd agreed to take the drivers into their homes. Archie wondered what the boss had promised in return.

The lack of motel vacancies had served as a warning. Archie dispatched his family that morning in the Buick station wagon to stay with his wife's sister in Troy, New York. Susan didn't like being separated from him, although she too maintained that nothing was going to happen. But she became visibly worried when Archie reported that Harrison took it all very seriously. We'll be back here next week joking about it, they'd agreed. Then she'd gotten into the Buick with their teenage son and daughter, both of whom had objected loudly to the forced removal, and driven off.

The convoy was moving at a brisk pace along the four-lane road. Now and then, Archie saw other caravans. Macro Electronics. Sonya Precision Timepieces. SolarWorks Complete Auto Power Systems. Occasionally clusters of new cars with dealer plates sped past.

Being out on the highway, watching people heading west, undercut Archie's self-assurance even more. "What do you think?" asked Claire.

"It's crazy," he said. But he knew he was saying it because he was a boss and skepticism was expected from him. "This is just the chief playing it very safe."

"I'm glad to hear you say it."

"I don't think there's anything to worry about." And a minute later: "Where's your family?"

"Home. We thought about going to my sister's for a few days, but it means pulling the kids out of school, and Ed couldn't get the day off."

"Yeah. I know how it is."

And after another long silence: "But I'll be glad when we're through it, Archie. The stuff on the TV scares me."

His cell phone beeped. "Pickman," he said.

"Archie, this is Brad." Brad Cabry was a staff assistant, riding at the rear of the convoy. "I don't know whether you've been listening to the radio, but they're saying traffic's already heavy on the Pennsylvania Turnpike. More than rush hour. They're cautioning people to stay off."

Archie looked out at the long line of cars and trucks ahead. "Too late for us," he said. "We'll stick with Plan A. If it takes all night, it takes all night."

Claire nodded. "Absolutely," she said. "I can use the overtime."

Archie shifted his weight and tried to get comfortable. The truck felt as if it had a broken spring. "Has this damned thing been serviced?"

She reached into the glove box, pulled out the maintenance record, and handed it to him. He looked down at the numbers, but he had trouble focusing on them. Manhattan. 3:36 P.M.

Marilyn Keep had looked at the pictures of jammed expressways, had watched news commentators smile condescendingly at the people who were on the run, had seen Chicken Little cartoons on New York Online. Anybody who was trying to head upstate was being portrayed as an idiot. Well, to those who were stuck in the city, it was comforting.

She was back working on Shadow of the Betrayer when the phone rang. It was Larry: "What are we doing tomorrow, love?"

She looked away from her chart, which recorded every physical and psychological detail of each character from the novel, and frowned at the phone. "Watching the Moon get plunked, I guess," she said. "What did you have in mind?"

"Louise is throwing a comet party tomorrow night. She'd like us to come."

"It's kind of last-minute, isn't it?"

"Well, it's kind of a last-minute comet. I think it'll be a kick."

Louise was one of Larry's colleagues, an economist at Kraus amp; Cole. Marilyn had socialized with her on a few occasions. She was twice divorced, a woman who claimed to have thrown out both husbands, although Larry said it had been the other way around. She was the unofficial office social director, putting together pot luck lunches, bowling teams, and mass trips to dinner theaters. "Sure," she said. "Let's do it."

The world seemed to have returned almost to normal. Late-night comics were doing comet jokes, and a TV preacher had announced that Tomiko had been headed originally for Alabama until he'd prayed it away. Political pundits were analyzing its effect on the fall campaign. (Most thought it would hurt Haskell's chances, despite what they perceived as his adroit grandstanding, because of the national investment in Moonbase, which was now irrevocably lost.) The Yankees, who were at home this weekend against the Tigers, announced that if the Saturday night game had not yet been completed by ten thirty-five, the time of impact, they would call a delay to proceedings and put the celestial show on the replay screens. The Moon would be in the west, not visible to the fans other than those in the right-field seats. Some fans objected, and suggested that management could put the show on the screen, but that was no reason to hold up the game.

Marilyn's third-floor apartment looked out across Central Park. Everything seemed as it always did: A couple of kids were trying to fly a kite while their mothers looked on, joggers moved along the pathways, and the usual number of people occupied benches. Panhandlers were working pedestrians, and the streets were filled with taxis, buses, and delivery trucks. The schools were open, and Wal-Mart had announced a big comet sale. ("Get your tail down here while the savings last.")

Shadow of the Betrayer struck her as one of the less imaginative murder mysteries to arrive on her desk. The killer was transparently visible from about Chapter Three, and only marginally motivated. The red herrings were all quite plainly red herrings. The pacing was off, the characters were dull. The narrative had a breakneck quality out of keeping with what should have been an atmospheric mystery. The reader never had time to stop and think about implications. And the novelist himself seemed to have missed several opportunities to create real drama. It was as though he'd been double-parked.

Unable to concentrate, she opened the balcony door and stepped outside. It wasn't much of a balcony, just big enough to accommodate two chairs and a small table. She stood for a while, leaning against the concrete rail, watching three men move furniture from a rented truck into the apartment building next door. San Francisco. 1:20 P.M. Pacific Daylight Time (4:20 EDT).

Everybody in the third-floor office of Bennett amp; McGee was staring at the TV. It was a split screen. A map of the Bay Area filled one side, from Richmond in the north to Santa Clara and the Los Altos Hills in the south, from the Pacific over to I680, encompassing more than eleven hundred square kilometers. An image of the comet's head, somewhat longish and irregular, cratered and torn, occupied the other. One huge crater took up about a fifth of the comet's visible surface. While Jerry watched, the outline of the Bay Area was superimposed over the comet nucleus. Then it was reduced until San Francisco and environs fit neatly into the big crater. A legend blinked on at the bottom of the screen: ACTUAL SIZE.

In a voice-over, Senator Mark Caswell was speaking with PugetWeb anchor Jane McMurtrie.

"… impeachment," he was saying. "It's absolutely unthinkable that a president of the United States would downplay this kind of threat. I think you'll see an appropriate congressional response in the near future."