For Janet
PROLOGUE
Lida Mae
The warning alarm woke Lida Mae from the deepest of sleep. Its wail was like a cross between an air-raid siren and a foghorn, and Lida Mae knew instantly what it meant, even though she’d never heard it before. Lida Mae was twelve; the alarm had never before sounded in her lifetime. If her parents and grandparents were to be believed, it hadn’t gone off in centuries, not since it was first installed.
Lida Mae sprang from the pallet where she’d been sleeping and rushed to the nearest security screen embedded in rock. Her family had always been people of the woods, people who chose to live in a cave. She knew as well as anyone that this could be a false alarm caused by a squirrel or a raccoon or a bat chewing a wire. The death squawk of an inferior creature.
But the security footage flowing across the screen showed two children, a boy and a girl, standing before a broken desk in a sterile room. While Lida Mae watched, the children lifted papers from inside the desk, sank to the floor, and began to read. The children both had dark hair and dark eyes, which grew more and more solemn the longer they read. They both wore jeans and flannel shirts. The girl wore a hooded sweatshirt, too, but Lida Mae could still tell that both kids hunched their shoulders the exact same way. Perhaps these kids were twins. Perhaps they were about Lida Mae’s age. Perhaps, in another lifetime, under different circumstances, she might have met them on a playground and they would have become fast friends.
She could sense her family crowded behind her, watching too, over her shoulder. But they stayed a respectful distance away. She had been first up, first to respond. This was her responsibility.
“Have you . . . ?” her mother murmured.
“Not yet,” Lida Mae said, although she couldn’t have explained what she was waiting for. A sign from the children, maybe, some indication whether they would be enemies or friends, just by their very nature.
She drew in a breath, preparing to speak a command, when the children on the screen suddenly looked up, startled. Lida knew they were only staring at the door of their sterile room, but it felt like they were staring at her; it felt like the surprise and fear mingled in their expressions were her fault. They scrambled to tuck the papers they’d been reading into their clothes, out of sight. Either they didn’t know who was coming for them, or they did, and they were terrified.
The door of their room opened, letting in four adults and two more children. The room was full now, crowded with hugs and scoldings Lida Mae could sense without quite hearing.
Family, she thought. That’s how families behave.
She managed to make out names from the faulty audio of the security system. The first two children who’d arrived in the room with the broken desk were Nick and Eryn. The other two were Ava and Jackson.
“Child . . . ,” her mother prompted from behind her.
“I know,” Lida Mae said. She squared her shoulder, lifted her chin, and addressed the security screen. “Analyze.”
It felt like the security screen was thinking, though Lida Mae understood that this was a fanciful view of things. The security camera was linked to only the most primitive of computers. It was capable of only the most rudimentary calculations; it could no more think than a chicken with clipped wings could fly.
“The first two children—human,” a voice devoid of emotion sounded from the screen. “The other two—robots. All the adults—robots.”
Lida Mae’s family gasped behind her.
“That’s . . . complicated,” her mother whispered.
“I can handle it,” Lida Mae said, standing up straighter, taller. “I’ll take care of everything.”
ONE
Ava
Ava tried to catch her twin brother as he fell.
She and Jackson had been walking with the rest of their family through a dark cave, away from the odd room where they—and their stepsiblings—had learned a dangerous secret. Ava could tell Jackson was off-kilter. Thanks to her illegally enhanced vision, she could see him weaving and squinting and grimacing even though there wasn’t enough light for anyone else to notice. His sandy-brown hair flopped around like a distress flag.
“Jackson, be careful!” she hissed. “Just stop thinking about—”
He was already stumbling, already dropping to his knees, already plunging face-first toward the rocky ground.
Ava grabbed for him, managing to catch his elbow with one hand and his armpit with the other. A year ago, when she and Jackson were both roughly the same size, that would have been enough for her to hold him up. But Dad had studied human growth charts, and he’d designated age twelve as the time when his son should grow five inches taller than his daughter and put on twenty pounds of muscle mass.
Well, not exactly muscle, Ava corrected herself, even as she cried, “Mom! Help! Jackson is . . .”
Mom reached for Jackson from the other side, but it was too late, and they were all too unbalanced. Gravity took over. Mom and Ava slammed to the ground along with Jackson.
“Oh no! Ava, Jackson, are you okay?” Mom cried, her first concern the children’s well-being, as always. It was maddening. “Someone, please, a flashlight . . .”
Immediately Ava, Mom, and Jackson were caught in a ring of light. Even Ava’s superior vision was temporarily blinded by the glow, so she couldn’t see who was training a flashlight on Jackson’s embarrassing moment and who was just standing there gawking. But she could count shoes, and everyone had circled around the piled-up Lightners: Ava’s stepsiblings, Eryn and Nick Stone, who were also twelve-year-old twins; Dad and his new wife, Denise, who was Eryn and Nick’s mother; and Denise’s ex-husband, Donald, who was the other kids’ father.
Oh, yeah, we’re just like a traveling circus troupe, Ava thought. Come one, come all, to see the happy blended family! Stepparents, stepchildren, stepsiblings—everyone getting along!
Ava truly hoped they could all get along. But that seemed impossible now, given the papers she’d seen Nick tuck under his flannel shirt when the rest of the family found him and Eryn in the cave’s secret room.
“Zzzt, zzzt,” Jackson said, quivering as if he was totally shorting out. It was a sound that made Ava feel queasy and dizzy and in danger of falling apart herself.
Don’t listen, she told herself. Tune it out. Pretend . . .
Pretend she was normal. Pretend she was just an ordinary kid. Pretend she was human. Like Eryn and Nick.
“Is he . . . broken again?” Eryn asked, taking a step back.
Ava wished her vision weren’t quite so good. She wished she couldn’t see the disgust on Eryn’s pretty, normal, human face.
“Can anyone fix him, way out here in the middle of nowhere? In a cave?” Nick asked. Ava tried to give him the benefit of the doubt: Maybe he actually cared. Maybe he was trying to help. Not just pointing out how weird and troublesome Jackson was. “Don’t you need electricity or something?”
He made electricity sound bizarre and risky and outlandish.
If Jackson were upright and alert right now, he’d probably have a snappy comeback, maybe, Oh, and you don’t ever use electricity yourself? But Dad had programmed Ava to be more sweet and kind than that. She couldn’t do snappy comebacks without worrying that she’d hurt someone’s feelings.
Or maybe she’d learned that from Mom.
“Don’t worry,” Mom said, shoving back her curly red hair, which was just a little longer and thicker and more flamboyant than Ava’s. Mom smiled reassuringly up at Nick and Eryn. “Any of us adults can help Jackson. We just have to, uh . . .”
She pointed to her stomach and pantomimed opening her coat and shirt.
Ava scrambled up and away from Mom and Jackson, almost crashing into Eryn, just as
Eryn shoved her flashlight into her dad’s hands and turned her head and took a step back.
Eryn was trying to get away from Mom and Jackson too.
“Ugh, Mom, do you have to talk about it?” Ava asked. “And please don’t do that in public! Not when you have to expose your . . .” She stopped herself from saying “wires.” She knew Nick and Eryn already knew that Mom—and all the other adults and Ava and Jackson—had wires and circuitry hidden inside their bodies, in all the places where Nick and Eryn had normal human organs and blood vessels and bones. But, knowing Mom, she’d probably try to turn the rebooting of Jackson into a science lesson for the kids.
So humiliating.
“Ava, we’re hardly in ‘public,’ ” Dad scolded. “We’re in a cave that doesn’t show up on any map, surrounded by a fifty-two-thousand-acre nature preserve that nobody but our family has visited in more than a decade. We’re safe.”
“Except for the possibility of sinkholes and rockslides,” Ava muttered, which made Nick almost grin at her.
Almost.
Ava envied Eryn her normal-human-girl vibe—like the way she could roll her eyes without the slightest mechanical hesitation. But Nick seemed more likable. More sympathetic.
“Ava, you’re reaching an age where it’s understandable for you to have concerns about the changes in your own body,” Ava’s stepmother, Denise, said, in her usual middle-school-psychologist soothing voice. “It’s perfectly natural for preteens like you to transfer some of that anxiety into embarrassment over your parents’ bodily natures. But there’s nothing to be ashamed of.”
Ava did not envy Nick and Eryn, having their every move psychoanalyzed and explained to them their entire lives. Since Dad and Denise had gotten married, six months ago, Ava had learned to avoid Denise as much as possible.
“Why don’t the three kids go sit over there while Jackson reboots?” Denise’s ex-husband, Donald, suggested, pointing toward a vaguely couch-shaped rock off to the side. “That’ll give Brenda more space to work.”
Ava liked how he made it sound like it would be a kindness—not cowardice—for the kids to walk away. She didn’t know Donald well, but she would have preferred him as a new stepparent over Denise.
Maybe he and Mom . . . ? she thought.
She made the mistake of glancing from Donald to Mom again. Mom was bent over Jackson and had started unzipping her coat. Ava’s head went woozy.
It’s not embarrassment over my parents’ “bodily natures,” Ava thought. It’s that Mom’s body isn’t real. It isn’t human. Just like my body isn’t human. And Jackson’s body isn’t . . .
“Go on,” Donald said, giving Ava a gentle nudge. “You’ll be okay.”
Eryn and Nick hesitated, but Donald gave them a push too, and they followed Ava toward the rock. Still, none of them sat down. Eryn and Nick slid their hands into their jeans pockets and hunched their shoulders. Probably they were just trying to stay warm, since they’d both left their coats back at the campsite, outside the cave. But the identical motion made them seem sneaky, maybe even conspiratorial. Ava saw them dart glances at each other.
They’re both human, and I’m not, Ava thought. I’m outnumbered. Defenseless. What if . . . what if they decide to follow the instructions on the papers hidden under Nick’s shirt?
For the first time since the odd room, she let herself think about the evil words she’d seen written on one of the papers—evil words about how humans needed to destroy robots.
Evil words essentially telling Eryn and Nick that they needed to kill Ava, Jackson, Mom, Dad, Denise, Donald—and everybody else who wasn’t human.
Maybe . . . maybe that isn’t really what it said, she told herself, fighting dizziness and queasiness and the urge to tumble senselessly to the ground, just like Jackson. I saw those words for only a moment before Nick hid the papers. I don’t think any of the grown-ups even saw that he had papers. Maybe . . . maybe I was just imagining things. Maybe my vision isn’t as good as I thought. Maybe I misread everything. Maybe . . .
It was too hard to fight her own brain. She knew what she’d seen. Her vision swam; her mind sizzled. Her hearing zoomed in and out. In a second she was going to be flat on the ground, making zzzt, zzzt sounds herself.
“Did you just hear something?” Nick asked, cocking his head. “Like maybe . . . footsteps?”
Ava seized on this question as if he’d thrown her a lifeline. She tilted her head too, forcing herself to listen intently. For a moment she couldn’t hear anything over the mechanical buzzing that had started in her ears, another sign that her system was going down. But she and Jackson had upgraded their hearing at the same time that they’d improved their vision, so she told herself that she owed it to her entire family to listen harder, to be their first line of defense.
She owed it especially to Jackson, who would really be in danger if any outsider saw him with all his innards exposed.
There, she thought, peering at a point off in the darkness. That’s where the sound’s coming from. The footsteps.
The noise seemed about as far away as if she were standing in the goal of a soccer field and the goalie at the other end was tiptoeing around. She took two steps toward that distant point, then changed her mind. No matter who—or what—she and Nick had heard, she couldn’t let anyone else find out how strong her vision was. She retreated all the way back to the three adults clustered around Jackson and Mom, and grabbed her father’s flashlight.
“Eryn and Nick and I need this for a minute,” she muttered.
In a flash she was back by Eryn and Nick’s side. She wasn’t going to faint. Not with this distraction. Not when she needed to protect her family. She linked her arms through the other two kids’ elbows.
“Let’s go see what it is,” she whispered.
“It’s probably just some kind of animal,” Nick said, his voice full of bravado. “Won’t it just run away when we get close?”
Ava could tell that he wished whatever it was would just run away. He didn’t need anything else to worry about tonight.
“It better not be a skunk,” Eryn muttered.
Ava took four more steps toward the spot she’d pinpointed as the source of the footsteps. The footsteps hadn’t sounded again since she’d grabbed the flashlight. Which meant whatever it was had frozen in place, rather than fleeing.
Because it doesn’t know that in another step or two, now that I’m listening closely, I’m going to be able to hear it breathe, she thought. Unless it’s smart enough to hold its breath.
Or maybe it was something that didn’t have to breathe?
Ava and the other two kids took two more steps forward. Then a third. Ava narrowed her eyes.
Oh no. Oh no. Eryn is going to wish it was just a skunk. . . .
But she didn’t say anything to the other two kids. The three of them kept walking forward, the flashlight in Ava’s hand casting its glow closer and closer to the distant point where they’d heard footsteps.
Oh, good grief, Ava thought. How blind are Eryn and Nick? Do they both need glasses?
Finally, a dozen steps later, Nick gasped.
“Is that . . . is that a girl?” he asked.
TWO
Eryn
Or a ghost? Eryn thought, because it was easier to start believing in ghosts than to accept that anyone else had found the secret cave that only Eryn’s family was supposed to know about.
What if somebody else had also found the secret room and seen the secret papers Nick had swiped and stuffed under his shirt? What if somebody else decided to follow their awful instructions?
Eryn had been raised by robots. She didn’t believe in ghosts.
She remembered the terrifying thought she’d had in the secret room, about how there might be killer robots hidden in the back of this enormous, possibly endless cave—killer robots left over from a time when robots had destroyed humanity, and the last humans of that era had had to resort to a risky, desperate plan involving frozen embryos and kind, careta
ker robots to revive the species.
But now the papers under Nick’s shirt said that even the caretaker robots were dangerous and had to be destroyed. Even the robots like Eryn’s parents. And Ava and Jackson. And . . . this girl?
Though her heart thumped frantically and she knew she wasn’t brave enough to take another shock, Eryn peered closely at the face caught in the beam of Ava’s flashlight. It was hard to tell in such dim light, but the girl’s eyes didn’t seem to have the flat, fake sheen Eryn had learned to look for in robotic eyes.
“Oh, um . . . hello,” the girl said, turning her head side to side to grin at all three of them. The movement was smooth, without any of the slight mechanical jerkiness Eryn associated with robots. “I’m Lida Mae Spencer. Who are all of you’uns? Where did you come from?”
The girl’s voice had an old-fashioned twang that made Eryn think of hoedowns and barn raisings and quilting bees. The girl sounded and looked and moved like a real human being—not a ghost, not a robot, killer or otherwise. But it felt like something else just as impossible was true: that this girl, Lida Mae, had stepped out of the pages of Eryn’s history textbook.
Beside Eryn, Ava lowered the flashlight, probably to be kind and direct the brightest part of the beam away from Lida Mae’s eyes. Now Eryn could see that Lida Mae had long braids hanging down on either side of her thin face. She wore a thick gray wool sweater—possibly handmade—and odd, bunched-up pants that might have been cut down from a pair that had originally belonged to an older brother or father. Her boots were dead ringers for the kind kids wore in Little House on the Prairie.
Maybe Eryn was slow in absorbing all of this. Nick answered before she or Ava could get a word out.
“Uhhh . . . hi. I’m Nick, and that’s my sister, Eryn,” he said, pointing. “And my stepsister, Ava. And we’re here because, uh . . .”
Wait—was he going to try to explain? Would he be stupid enough to tell the truth?
“Our family’s on a camping trip,” Eryn said quickly. “That’s all.”