Lightning

'What way?'

The boy screwed up his face and squinted through the windshield at the snow and moon glow and darkness ahead. 'See, Mom, as soon as they lost us, they'd push the buttons on their belts, go home to the future, and then make a new trip back to our time to set another trap for us. They knew we took this road. So what they probably did was make another trip back to our time, but earlier tonight, and, they set a trap at the other end of this road, and now they're waiting there for us. Yeah, that's where they are! I'll just bet that's where they are.'

'But why couldn't they come back even earlier tonight, earlier than they came the first time, back to the house, and attack us before my guardian ever showed up to warn us?'

'Paradox,' the boy said. 'You know what that means?'

The word seemed too complex for a boy his age, but she said, 'Yes, I know what a paradox is. Anything that's self-contradictory but possibly true.'

'See, Mom, the neat thing is that time travel is full of all kinds of possible paradoxes. Things that couldn't be true, shouldn't be true — but then might be.' Now he was talking in that excited voice with which he described scenes in his favorite fantastic films and comic books, but with more intensity than she had ever heard before, probably because this was not a story but reality even more amazing than fiction. 'Like suppose you went back in time and married your own grandfather. See, then you'd be your own grandmother. If time travel was possible, maybe you could do that — but then how could you have ever been born if your real grandmother had never married your grandfather in the first place? Paradox! Or what if you went back in time and met up with your mom when she was a kid and accidentally killed her? Would you just cease to exist— pop! — like you'd never been born? But if you ceased to exist — then how could you have gone back in time in the first place? Paradox! Paradox!'

Staring at him in the moon-painted darkness of the Jeep, Laura felt as though she was looking at a different boy from the one she had always known. Of course, she had been aware of his great fascination with space-age tales, which seemed to preoccupy most kids these days, regardless of age. But until now she hadn't gotten a deep look inside the mind shaped by those influences. Evidently the American children of the late twentieth century not only lived interior fantasy lives richer than those of children at any other time in history, but they seemed to have gotten from their fantasies something not provided by the elves and fairies and ghosts with which earlier generations of kids had entertained themselves: the ability to think about abstract concepts like space and time in a manner far beyond their intellectual and emotional age. She had the peculiar feeling that she was speaking to a little boy and a rocket scientist coexisting in one body.

Disconcerted, she said, 'So… when these men failed to kill us on their first trip tonight, why wouldn't they make a second trip earlier than the first, to kill us before my guardian warned us that they were coming?'

'See, your guardian already showed up in the time stream to warn us. So if they came back before he warned us — then how could he have warned us in the first place, and how could we be here where we are now, alive? Paradox!'

He laughed and clapped his hands like a gnome chortling over some particularly amusing side-effect of a magical spell.

In contrast to his good humor, Laura was getting a headache from trying to sort out the complexities of this thing.

Chris said, 'Some people believe time travel isn't even possible 'cause of all the paradoxes. But some believe it's possible so long as the trip you make into the past doesn't create a paradox. Now if that's true, see, then the killers couldn't come back on a second, earlier trip 'cause two of them had already been killed on the first trip. They couldn't do it because they were already dead, and it was a paradox. But the guys you didn't kill and maybe some new time travelers could make another trip to cut us off at the end of this road.' He leaned forward to peer through the streaked windshield again. 'That's what all that lightning was off to the south when we were weaving to keep them from shooting us — more guys from the future were arriving. Yeah, I'll bet they're waiting for us down there somewhere, down there in the dark.'

Rubbing her temples with her fingertips, Laura said, 'But if we turn around and go back, if we don't drive into the trap ahead, then they'll realize we've outthought them. And so they'll make a third trip back in time and return to the Mercedes and shoot us when we try to drive back that way. They'll get us no matter which way we go.'

He shook his head vigorously. 'No. Because by the time they realize we're on to them, maybe half an hour from now, we'll already have turned around and driven back past the Mercedes.' The boy was bouncing up and down in his seat with excitement now. 'So if they try to make a third trip in time to go back to the beginning of this road and trap us there, they can't do it, because we'll already have driven back that way and out, we'll already be safe. Paradox! See, they got to play by the rules, Mom. They're not magical. They got to play by the rules, and they can be beat!'

In thirty-three years she had never had a headache that had gone from a mild throb to a pounding skull- splitter as quickly as this one. The more she tried to puzzle out the difficulties of avoiding a pack of time-traveling hitmen, the deeper rooted the pain became.

Finally she said, 'I give up. I guess I should've been watching Star Trek and reading Robert Heinlein all these years instead of being a serious adult, because I'm just not able to cope with this. So I'll tell you what: I'm going to rely on you to outsmart them. You'll have to try to keep one step ahead of them. They want us dead. So how can they try to kill us without creating one of these paradoxes? Where will they show up next… and next? Right now, we're going to go back the way we came, past the Mercedes, and if you're right, no one will be waiting there for us. So where will they show up after that? Will we see them again tonight? Think about those things, and when you have any ideas, let me know what they are.'

'I will, Mom.' He slumped down in his seat, grinning broadly for a moment, then chewing on his lip as he settled deeper into the game.

Except it was not a game, of course. Their lives were really at stake. They had to elude killers with nearly superhuman abilities, and they were pinning their hopes of survival on nothing more than the richness of an eight- year-old boy's imagination.

Laura started the Jeep, put it in reverse, and backed up a couple of hundred yards until she found a place in the road wide enough to turn around. Then they headed back the way they had come, toward the Mercedes in the ditch, toward Big Bear.

She was beyond terror. Their situation contained such a large element of the unknown — and unknowable — that terror could not be sustained. Terror was not like happiness or depression; it was an acute condition that by its very nature had to be of a short term. Terror wilted fast. Or it escalated until you passed out or until you died of it, frightened to death; you screamed until a blood vessel burst in your brain. She wasn't screaming, and in spite of her headache she didn't think any vessels were going to burst. She settled into a low-key, chronic fear, hardly more than anxiety.

What a day this had been. What a year. What a life.

Exotic news.

2

They passed the stranded Mercedes and drove all the way to the north end of the ridge road without encountering men with submachine guns. At the intersection with the lakeside highway, Laura stopped and looked at Chris. 'Well?'

'As long as we're driving around,' he said, 'and as long as we go to a place where we've never been and don't usually go, we're pretty safe. They can't find us if they don't have any idea where we might be. Just like your regular-type scumbags.'

Scumbags? she thought. What is this — H. G. Wells meets Hill Street Blues'!

He said, 'See, now that we've given them the slip, these guys are going to go back to the future and look