“I’d forgotten that you knew Dr. Benoît,” said Krieger.

Mary shook her head in amazement. “You’re a one-man brain drain, Jock.” She looked again at Louise, wondering how anyone could be so radiant without makeup. “It’s good to see you, Louise.” And then, the cat in her coming to the fore, “How’s Reuben?”

Reuben Montego was the on-site physician at the Creighton Mine. Louise had had quite a torrid little affair with him while Mary, Ponter, Reuben, and she were all quarantined in Sudbury. Mary had assumed they were simply passing time, so she was surprised by Louise’s response. “He’s fine,” she said. “He helped me move my stuff down here, and I’m going up to see him again next weekend.”

“Ah,” said Mary, realizing she’d been put in her place. “And what’s your job here?”

“Dr. Benoît is heading our Portal Group,” said Krieger.

“That’s right,” said Louise. “We’re trying to work out the technology to open a portal from our side into the other universe.”

Mary nodded. Louise hadn’t spent all her time making love with Reuben; she’d also had many long late-night conversations of her own with Ponter Boddit, and doubtless knew more about the Neanderthal view of physics than anyone else on this version of Earth. Mary was ashamed of herself; Louise had never done anything to her—her only crime was being beautiful. “It’ll be nice to spend some time with you again,” said Mary.

“Say,” said Louise, “I could use a roommate down here. What do you think? We seemed to get along well when we were quarantined at Reuben’s.”

“Umm, no,” said Mary. “No thanks. I, ah, I like my privacy.”

“Well, you’ll have no trouble finding a place here in Rochester,” said Louise.

Krieger nodded. “Both Xerox and Kodak have had a lot of layoffs in the last few years, and they’re the city’s principal employers. You can buy houses for a song, and you’ll have your pick of hundreds of apartments.”

“Good to know,” said Mary.

“Try Bristol Harbour Village,” said Louise. “It’s an hour from here, but it’s right on one of the Finger Lakes. Gorgeous. Lots of deer, and you can see the stars at night.”

“Speaking of night skies,” said Mary, realizing Louise might be the one to ask about this, “on my last night in Sudbury, I saw the aurora borealis go nuts. What would cause that?”

Louise looked at Mary for a few seconds, as if she couldn’t believe the question. “Haven’t you seen the newspapers?”

Mary shook her head. “I’ve been busy getting ready to move here.”

“Earth’s magnetic field is behaving erratically,” said Louise. “Readings from all over the globe confirm that. The geodynamo strength is fluctuating substantially.”

“What could cause that?”

Louise shrugged. “No one knows.”

“Is it dangerous?”

“Probably not.”

“Probably?” said Mary.

“Well,” said Louise, “nothing quite like this has ever been recorded. There are a number of experts who think that Earth’s magnetic field is collapsing, as a prelude to a pole reversal.”

Mary had heard vaguely of these, but she was pleased that Krieger was the one who said, “Which is?”

“Earth’s magnetic field switches polarity from time to time—you know, the north pole becomes the south pole, and vice versa,” said Louise. “It’s happened over three hundred times in the geological record, but never in historical times, so we really don’t know much about the process. But it’s always been assumed that the reversals occur by the field collapsing, then growing back up again.”

“And you say there’s nothing to worry about,” said Krieger. “It’s not associated with mass extinctions, is it?”

Louise shook her head. “No. The field was actually reversed from its present orientation at the time the dinosaurs died out, but it had been in that state for over a million years before the end of the Cretaceous.” She smiled that mega watt smile. “The worst thing we’ll have to do is repaint our compasses.”

“That’s a relief,” said Mary.

Louise nodded. “And even that may not be necessary,” she said. “As far as we can tell, which pole ends up being north and which one ends up being south is determined quantum mechanically, meaning it’s entirely random—and that means there’s only a fifty-fifty chance of the field reemerging with its polarity reversed.”

Krieger raised his eyebrows. “But if that’s true, then if there’d been a magnetic-field collapse when the dinosaurs died out, we wouldn’t know about it if the field had come up with the same polarity it had had before.”

“You’re worrying for nothing, Jock,” said Louise. “The magnetic-field collapses that we do know about aren’t associated with extinctions. So it doesn’t make any sense to assume that the ones that we missed, because the field happened to come up with the same polarity it had before it collapsed, had any biological effects.” She smiled at Krieger, who, Mary noted, still seemed lost in his own thoughts. “Don’t worry,” Louise said, “I’m sure we’ll all come through this one just fine.”

“You told me earlier,” said Jurard Selgan, “that your sole interest in seeing the portal reopened was in bringing benefits to the people of our world.”

Ponter nodded curtly. “That’s right.”

“And since the ability to be in contact with that other world depended on the quantum computer that you had developed with Adikor Huld, naturally you would stay here, on this Earth, helping to oversee the quantum-computing facility.”

“Well…” began Ponter, but then he trailed off.

“You did say you had no personal interest in this issue, didn’t you?”

“Yes, but—”

“But you fought the High Gray Council yet again, didn’t you? You insisted that you personally be allowed to return to the other Earth.”

“It was the only thing that made sense,” said Ponter. “No one else from our world had ever been there. I knew some of the people, and had learned a great deal about their world.”

“And you refused to transfer the Gliksin linguistic database your Companion implant had gathered to anyone else unless you were guaranteed the right to be part of the next group traveling to the other world.”

“It wasn’t like that,” said Ponter. “I merely suggested that my presence would be useful.”

Selgan’s tone was gentle. “You did more than just ‘merely suggest,’” he said. “Like most of the world, I saw much of this on my Voyeur. If your own memory of the events has faded, we can easily access your alibi archives from that day. That’s why my therapy center was built here, close to the Alibi Archive Pavilion. Shall we go over there and—”

“No,” said Ponter. “No, that won’t be necessary.”

“So you did use—is ‘coercion’ too strong a word?—to get yourself back into the other world?”

“I wanted to make the greatest possible contribution I could. The Code of Civilization requires that of each of us.”

“Yes, it does,” agreed Selgan. “And if that contribution—if the greater good—could best be served by committing a crime, well, then…”

“You’re wrong,” said Ponter. “I hadn’t even contemplated my crime yet. My only goal…” He paused, then continued. “My only goals were to help with continued contact, and, yes, to see my friend Mare Vaughan. I never would have gone over there if I’d known what I was going to end up doing…”

“That’s not entirely true, is it?” said Selgan. “You said even if you had the opportunity to relive the moment of your crime, you still would have committed it.”

“Yes, but…”

“But what?”

Ponter sighed. “But nothing.”

The High Gray Council had finally acquiesced to Ponter’s demand that he be allowed to leave the quantum computer in Adikor’s care, so that he could return to the Gliksin world. He’d expected a reluctant agreement—and he was sure that was what it was—but he hadn’t expected to have the title of “Envoy” bestowed upon him