“Totally scrambled up in our kids,” said Ivy-Z. “They don’t know who’s coming and who’s going.”

  “They both can side step?” asked Ivy.

  “They both can breathe. And many other small talents,” said Ivy-Z.

  “You know what I’m asking,” said Laz.

  “Ron’s people would love to tell him my answer to that offensively dangerous question.”

  “They don’t know?” asked Ivy. “How? Do you and your Laz communicate telepathically?”

  Ivy-Z looked at her with scorn, then looked away.

  “How are we supposed to know what you two might have developed before you even had kids?” asked Ivy. “Maybe you can all fly. Maybe you can make new timestreams.”

  “Everybody makes new streams all the time,” said Ivy-Z. “Without knowing it, without meaning to, every choice they make or don’t make reshapes the causal universe.”

  “So who is taking all the threads in hand and making sure they don’t spill into each other?” asked Laz. “God?”

  “If somebody could do that, then they’d pretty much have to be God, or close enough as not to matter,” said Ivy-Zero. “But we haven’t seen the man behind the curtain. Or, for that matter, the curtain itself.” And then she thought of something. “Do you kids even know The Wizard of Oz?”

  “1939 movie or book?” asked Ivy. “Please not that horrible 2030 remake with that ridiculous AI Tin Man.”

  “Oh,” said Ivy-Zero. “Of course you know Oz because I read the book and saw the movies before I was even in middle school.”

  “For what it’s worth,” said Laz, “I don’t give a rat’s ass about Oz.”

  “If they were going to make a CGI Tin Man, couldn’t they have made it dance better?” asked Ivy.

  “Let’s take a walk,” said Ivy-Z.

  “What good will that do?” asked Ivy. “They probably have listening devices implanted in all your clothing.”

  “Maybe I want to take a walk because I need to let the dogs back into the yard,” said Ivy-Zero.

  “You let them out of the yard?” asked Ivy. “Do you hate your neighbors?”

  “These aren’t the original Pack of Four that you guys remember,” said Ivy-Z. “Those dogs died. Ron’s people gave them noble-looking headstones right in the human cemetery in this town. The dogs now are four that we raised from unrelated puppies and trained to be obedient. They have no memories of being feral… or of being hit with fast-moving stones. And none of them are named for brands of tuna fish. Or Renaissance artists. Or famous movie dogs.”

  “What are their names, then?” asked Laz.

  “We rejected Marat, Robespierre, Napoleon, and Dreyfus,” said Ivy-Z. “What did we care about French history?”

  “Oh, thanks for telling us the rejected names,” said Ivy. “Now we’re four names closer to figuring out which of the millions of available names you opted for.”

  “Wow,” said Ivy-Z. She looked at Laz. “If she’s always that bitchy, why do you keep her around?”

  “Because I usually agree with her bitchiness,” said Laz. “And she lets me kiss her.”

  “Reasonable points,” said Ivy-Z.

  Out of the house, out of the yard, the three of them walked up the one-lane road, saying nothing. Ivy-Z was carrying four leashes, but Laz suspected they were for show. If the dogs were really well trained, they’d fall into position and accompany her home.

  Then Laz saw the dogs. Nothing like the Pack of Four. Two spaniel-looking dogs, a yappy mutt poodle, and a confused-looking Australian shepherd—supposedly the smartest dog breed. Ivy-Zero introduced them as Ulysses, Tecumseh, Jubal Early, and Robert E. Lee. Ivy looked baffled, so Laz explained. “Civil War generals. Ulysses Grant, William Tecumseh Sherman, Jubal Early—”

  “I think that’s one of the best names ever given to an American,” said Ivy-Zero.

  “And Robert E. Lee,” said Laz.

  “And you know this because…”

  “I paid attention in history class.”

  “No you didn’t,” said Ivy.

  Ivy-Zero said, “He was a Civil War buff. A whole library of audiobooks he listened to while walking all over LA County.”

  “Now I remember,” said Laz.

  “What did we come out here to discuss in privacy?” asked Ivy.

  “There is no privacy. I assume all the dog collars are wired.”

  “Then why did we come out here?” asked Ivy.

  “To bring the dogs back into the yard,” said Ivy-Z. “Like I told you.”

  “Are your children talented?” asked Laz softly. “I know the dogs aren’t.”

  “You’d be surprised,” said Ivy-Z. “But yes, our children are away from home to keep Ron’s people from studying them. Not that they’d do it invasively, just enough to know what abilities they each have. We don’t like the idea of our kids being studied like rodents in a maze. So it isn’t going to happen.”

  “And you manage to keep them hidden?” asked Ivy.

  Laz put his arm over her shoulder, “Ivy, my genius sidekick, we don’t know how many times they’ve side stepped to avoid any timestream in which the kids are caught.”

  “Side stepping makes us pretty slippery,” said Ivy-Zero.

  “How can you stand living away from your children?” asked Ivy.

  “They’re both in college. Abroad. Different universities in different countries with different academic languages.”

  “Do they have names?” asked Ivy.

  Ivy-Z slapped her forehead. “We could have named them?”

  Laz laughed. “Come on, Ron’s goons know the names you gave them at birth, and they know whatever names you called them around your well-wired home.”

  “We just don’t use their names,” said Ivy-Zero. “Now it’s a habit.”

  “I bet it also irritates Ron,” said Laz, “if you pretend not to know who he’s talking about when he says their names.”

  “Pretend?” asked Ivy-Z.

  “We need your help with something that just came up,” said Laz.

  “Just?” asked Ivy-Z.

  “Day before yesterday. I was in another timestream, creating a link between that one and another.”

  “Another preexisting timestream, I assume. Like this one,” said Ivy-Z.

  Of course all the Ivys saw all the Portals as they were made, thought Laz. “Yes,” he said.

  “A secret Portal, unknown to any government,” said Ivy-Z.

  “You know us so well,” said Ivy.

  “I assume you succeeded, to your own satisfaction.”

  “It was trickier than usual,” said Laz, “because Ivy wasn’t with me. I was ostensibly on vacation in the woods, away from this incredibly bossy woman.”

  “It’s perfectly credible,” said Ivy.

  “I was about to create a second one, a click or two away, but while I was tying the twine to the trunk of a tree, I completely missed someone coming up behind me.”

  “Who?” asked Ivy-Z.

  “We’re here to see if you can help us answer that,” said Ivy.

  “You didn’t see them, then,” said Ivy-Z.

  “Didn’t see, didn’t hear.”

  “So how do you know they were there?” asked Ivy-Zero.

  “Because when I turned around, a small patch of leafy ground had been cleared down to the dirt, and in that dirt, there was a message.”

  “A short, simple one, I assume,” said Ivy-Z.

  “No,” said Ivy, “it was a flashing neon sign.”

  “Don’t be an ass, Ivy,” said Laz.

  “So you’re the only one who gets to be an ass?” said Ivy.

  “What was the message?” asked Ivy-Z.

  “ ‘Laz No,’ ” said Laz. “Scratched in the dirt, like with a stick.”

  “And you didn’t hear them scratching it in the dirt.”

  “All I heard was my own shoes in the leaves at my feet. And I didn’t move much, I was quiet.”

  “So the message was already written there before you arrived,” said Ivy-Zero.

  Laz shook his head. “I have a picture. But look, even if I somehow didn’t notice it, I didn’t know where I was going to stop and make the Portal until I decided as I first walked into the clearing. How did somebody know I was going to be there? I didn’t even know.”

  Ivy-Zero nodded thoughtfully.

  “What is it you know that we don’t?” demanded Ivy.

  Ivy-Zero made a shrugging gesture with outstretched hands.

  Laz got it. “Mine wasn’t the first message,” he said.

  Ivy-Zero’s face became grave. “Messages scratched in the dirt,” she said. “We don’t even rate handwriting on the wall.”

  “What did your message say?” asked Ivy.

  “It was just as simple, really. It said, ‘Stop helping.’ ”

  Laz looked at Ivy, then at Ivy-Z. “That’s why you refused to make any more Portals?”

  “The only people we were helping were the Interplanetary Portal Commission,” said Ivy-Z. “So we stopped.”

  “But you didn’t know who sent the message, or why,” said Laz.

  “That’s right.”

  “How did you know—no, why did you believe that the message was from the good guys?”

  “I didn’t know. I still don’t,” said Ivy-Zero.

  “But you obeyed the message,” said Ivy.

  “I’m just a compliant person,” said Ivy-Zero.

  “In a pig’s eye,” said Laz.

  “Did you obey your message?” asked Ivy-Z.

  “Yes,” said Laz. “I figured I was being warned about something on the other side of the Portal. An ambush, a tar pit, an irritable hippo, a hundred angry guys with shotguns—”

  “But you didn’t know,” said Ivy-Z. “And you still don’t know.”

  “I didn’t want to risk moving into a timestream where I died too fast for me to step back out and get away.”

  “Prudent,” said Ivy-Z.

  “Timid,” said Ivy. “But that keeps him alive. And kept both of you—us—alive back in Greensboro.”

  “So this anonymous, invisible messenger gets us to do his bidding,” said Laz, “without explanation.”

  “Did you see your messenger?” asked Ivy.

  “No,” said Ivy-Z. “Laz—my Laz—was gathering up the dogs to bring them back to the yard, like we’re doing right now—earlier dogs, though—but when he got to the place where he was close enough to call the dogs, he looked down and right at his feet was the message, scratched in the mud at the side of the road.”

  “And how did they know he would stop right there?” said Ivy.

  “Same as you, Laz,” said Ivy-Z. “He swears the message wasn’t there when he first came up. It was only there when he looked down.”

  “And since he was facing toward it,” said Laz, “you two have no idea how the message got there.”

  Ivy-Zero shook her head. “I figured he just overlooked the writing in the half-dried mud.”

  “Didn’t trust his judgment,” said Laz.

  “Didn’t trust his alertness about what was on the ground when his attention was on the dogs across the meadow,” said Ivy-Zero, “but yes, my Laz resented my skepticism.”

  “Doesn’t matter,” said Ivy. “They still had to know, in advance, where he would stop to call the dogs—and where the dogs would be, for that matter. Still hard to explain. But you two have had a long time to think about it. Investigate it.”

  “Nothing to investigate,” said Ivy-Z. “When he brought the dogs home and then took me out to see the message, it wasn’t there. It had been smeared, like with someone’s shoe, so you couldn’t read the message but you knew something had been there. So I believed him about the message.”

  Ivy laughed. “Come on, you didn’t really believe him until my Laz told you his story.”

  “I didn’t think I doubted him, but yes, I was relieved to hear your story.”

  “And I was relieved to hear yours,” said Ivy.

  “I’m just as happy to find out that I wasn’t crazy,” said Laz.

  “Or if you were, you were exactly as crazy as your predecessor version of Laz,” said Ivy.

  “Not crazy,” said Ivy-Zero. “Don’t put doubt back into this, kid.”

  “No, you’re right,” said Ivy. “Here we’ve got two copies of the man considered to be the smartest in the world, they both experience something weird but nearly identical, and the question now isn’t whether a message came out of nowhere in an impossible place—impossible for anyone to know in advance—but how it got there. Both times.”

  “Any ideas?” Laz asked Ivy-Z.

  “Insane ones,” said Ivy-Zero. “Time travel, of course, but Laz himself—the original one, the scientist—he declared time travel to be impossible, and he had seen the timestreams.”

  “We already knew it was impossible,” said Ivy. “But it happened. We’re all sure that both messages happened.”

  “So where does that put us?” asked Ivy-Zero.

  “Here’s where we are,” said Laz. “We’re so sure that this stuff is impossible, but something must be possible because it happened. So maybe my smart famous genius original was wrong about time travel. Maybe somebody can see danger or bad results and then come back, scratch out a message in the dirt—”

  “Mud,” said Ivy-Z.

  “Without being detected,” said Ivy, “when the recipient of the message was right there. The message-writer is never seen or heard.”

  “Time travel can tell us how the messenger knew the message was needed, but not how it was done,” said Laz.

  “So, time travel and invisibility?” asked Ivy.

  “And utter silence,” said Ivy-Zero. “And incredible speed. But he didn’t bring paper, or write it on a stone and bring it with him. It seems like a crazy convoluted plan instead of just showing up, standing there, and saying, ‘Stop helping Ron,’ or ‘Don’t make a Portal here.’ ”

  Ivy nodded. “Only we’re making some assumptions of our own right now. When my Laz, this Laz, saw ‘Laz No,’ he assumed it referred to the Portal he was just beginning to create. But what if both messages were the same? What if the messenger was telling you guys and us to stop making Portals, or stop serving Ron and his guys, or something that had nothing to do with that actual Portal. Or maybe you guys’s message was trying to get you to stop helping somebody or some project that had nothing to do with Ron.”

  “The messages were pretty ambiguous,” said Laz.

  “And we have no other information to narrow it down,” said Ivy.

  “When your Laz gets home, you try to work this out with him, and we’ll keep trying to think of stuff, and maybe you bring your kids into the discussion.”

  “Or not,” said Ivy-Zero with an air of finality.

  “Unless you already know that your kids are the ones delivering these messages because they have time travel and invisibility and super speed and all that stuff,” said Ivy.

  “We have better and clearer ways to communicate,” said Ivy-Z. “And our children were still children when we got our message.”

  “When you stopped working with Ron,” said Laz.

  “And after a few years, when they finally believed that we weren’t changing our minds,” said Ivy-Z, “Ron woke you two up.”

  “All some cosmic misunderstanding,” said Ivy.

  “I like existing,” said Laz, “however it came about. But if the message wasn’t left by your young kids, it could have been left by your future kids, forty years from then.”

  “Thanks for pointing out that we know less than we thought we did,” said Ivy-Zero.

  “Being realistic,” said Laz.

  “Nothing about our lives is realistic,” said Ivy-Zero.

  Laz couldn’t argue with that.

  “Let’s go home,” said Ivy.

  “Thanks for talking to us,” said Laz to Ivy-Zero. “And for listening.”

  “Let’s go now,” said Ivy. “Before Ron gets here.”

  They left and Ron didn’t show up.

  They got home late and still had no idea how reality worked. They weren’t going to sleep much tonight.

  11

  LAZ LAY IN bed, unable to sleep because of the thoughts racing through his head. Or maybe he couldn’t sleep because of the day’s excitement, and so his brain came up with a bunch of dead-end thoughts to fill the time.

  How could a person be invisible? Molecules are molecules—they can’t suddenly start letting all the photons through. And what about clothes? Could the clothes be made invisible, too? H. G. Wells thought not, so invisibility had to be done naked. And that would be cold during the winter.

  In the summer, did invisible naked people drip with invisible sweat? Could you follow the trail of fresh sweat-drops to keep track of where they were?

  No such thing as invisibility. More likely that the messenger was incredibly quick. Except Zero-Laz’s message was scratched in the mud right at his feet. No matter how quick you were, Zero-Laz’s peripheral vision would have revealed something.

  No such thing as. Invisibility. Time travel. Super speed. Faster-than-light travel. Sound in a vacuum. Middle schoolers who could play the violin on pitch. Lots of impossible things.

  But side stepping into another timestream was impossible, too. Until it wasn’t.

  Laz thought of how the timestreams appeared. He didn’t visualize them, really, when he was looking for them or stepping into one. Yet in his mind, it seemed like there were millions of threads or strings extending from above, dangling in bunches or tangled ropes from a ceiling too high to be seen—or an infinite expanse of time past, and there was no beginning point at all. Didn’t matter right now.

  None of the streams reached the ground, which Laz and Ivy figured was because those timestreams were still being made, so there could be no time later than now.

  Except they did see a little way further along the timestream, into the future, so they could choose streams that didn’t end in sudden cataclysm. Ivy could see a little farther into the future than Laz, but they decided that this was because seeing the timestreams was the only thing that Ivy could do, so she practiced it and became more proficient than Laz, who never studied the future long, because he would find a timestream good enough for now, and side step.