Lightning

"They wouldn't want everyone to know they were from the future," Chris said. "They'd bring weapons and wear clothes that wouldn't be out of place here. But, Mom, he said he was from—"

"I know what he said. But it doesn't make sense, does it? If they had time travel in 1944, we'd know about it by now, wouldn't we?"

At one-thirty her guardian woke and seemed briefly confused as to his whereabouts. He asked for more water, and Laura helped him drink. He said he was feeling a little better, though very weak and still surprisingly sleepy. He asked to be propped up higher. Chris got the two spare pillows from the closet and helped his mother raise the wounded man.

"What is your name?" Laura asked. "Stefan. Stefan Krieger."

She repeated the name softly, and it was all right, not melodic but solid, a masculine-sounding name. It was just not the name of a guardian angel, and she was mildly amused to realize that after so many years, including two decades during which she had professed to have no belief in him. she still expected his name to be musical and unearthly.

"And you really come from—"

"Nineteen forty-four," he repeated. Just the effort required to move to a sitting position had wrung fine beads of perspiration from his brow — or perhaps the sweat resulted in part from thoughts of the time and place where his long journey had begun. "Berlin, Germany. There was a brilliant Polish scientist, Vladimir Penlovski, considered a madman by some, and very likely mad in fact — very mad, I think — but also a genius. He was in Warsaw, working on certain theories about the nature of time for more than twenty-five years before Germany and Russia collaborated to invade Poland in 1939…”

Penlovski, according to Stefan Krieger, was a Nazi sympathizer and welcomed Hitler's forces. Perhaps he knew that from Hitler he would receive the kind of financial backing for his researches that he could not get from sources more rational. Under the personal patronage of Hitler himself, Penlovski and his closest assistant, Wladyslaw Januskaya, went to Berlin to establish an institute for temporal research, which was so secret that it was given no name. It was simply called the institute. There, in association with German scientists no less committed and no less farsighted than he, financed by a seemingly inexhaustible river of funds from the Third Reich, Penlovski had found a way to pierce the artery of time and move at will through that bloodstream of days and months and years.”

"Blitzstrasse," Stefan said.

“Blitz — that part of it means lightning," Chris said. "Like Blitzkrieg — lightning war — in all those old movies."

Lightning Road in this case," Stefan said. "The road to the future."

It literally could have been called Zukunftstrasse, or Future Road, Stefan explained, for Vladimir Penlovski had been unable to send men backward in time from the gate he had invented. They could travel only forward, into their future, and automatically return to their own era.

There seems to be some cosmic mechanism that prohibits time travelers from meddling with their own pasts in order to change their present day circumstances. You see, if they could travel back in time to their own past, there would develop certain—"

“Paradoxes!" Chris said excitedly.

Stefan looked surprised to hear the boy speak that word.

Smiling, Laura said, "As I told you, we've had rather a long discussion about your possible origins, and time travel turned out to be the most logical. And in Chris here, you're looking at my resident expert on the weird."

"Paradox," Stefan agreed. "It's the same word in English and German. If a time traveler could go back in time to his own past and affect some event in history, that change would have tremendous ramifications. It would alter the future from which he had come. Therefore he wouldn't be able to return to the same world he'd left—"

"Paradox!" Chris said gleefully.

"Paradox," Stefan agreed. "Apparently nature abhors a paradox and generally will not permit a time traveler to create one. And thank God for that. Because. suppose, for example, Hitler sent an assassin back in time to kill Franklin Roosevelt and Winston Churchill long before they rose to high office, which would have resulted in the election of different men in the U.S. and England, men who might have been less brilliant and more easily dealt with, leading to Hitler's triumph by '44 or sooner."

He was speaking now with a passion that his physical condition would not allow him to sustain, and Laura could see it taking a toll of him word by word. The perspiration had almost dried on his brow; but now, although he was not even gesturing, a new thin film of sweat silvered his pale forehead again. The circles of fatigue around his eyes appeared to grow darker. But she could not stop him and order him to rest, because she wanted and needed to hear everything he had to say — and because he would not have allowed her to stop him.