Chapter One 

High overhead, the winged cryptogen circled tightly, its golden wings glinting in the sunlight that shafted through the clouds. 

Anaya squinted up at it, stunned. This was the last thing she’d expected to emerge from the ship that had just crash-landed. Not a runner, or a swimmer, but a flyer. 

The enemy. 

Where was Terra? Or maybe there had never been a Terra, or any rebels, and she’d been mistaken all along. Why had she trusted them? 

She’d stupidly thought this was going to be a peaceful encounter between humans and three cryptogen rebels, to form an alliance. To work together and make a weapon that would defeat their mutual enemy. 

That was a fantasy, a lie, and it was her fault. 

Terrified, she watched the flyer face off with the helicopter that had fired the missile. The spiky crest on the creature’s helmet shimmered with a sickly violet light and emanated an ominous whine. Even all the way down here, Anaya heard it. Everyone around her winced at the sound: Seth, Petra, Dr. Weber, Colonel Pearson, the lone soldier. She knew that whine could swell at any moment, to crush people and decimate buildings. 

“Why is there a flyer?” Pearson shouted at her. 

“I don’t know!” 

“Is that helmet a weapon?”

“Yes!” 

“They said they’d come unarmed!” 

--You attacked! 

This voice had never been inside Anaya’s head. Definitely it was not Terra’s. It came from the flyer. The words carried an angry whiff of gasoline and had a jagged metallic taste like she’d just bitten her own tongue. 

--It was a mistake! she called back desperately, and hoped the flyer believed her anguished words. 

“Don’t fire!” she shouted at Pearson, suddenly hopeful. “I’m talking to it.” 

“Tell the flyer to stand down!” Pearson barked. 

Anaya didn’t think they were in any position to give orders. 

“We fired first! We promised we wouldn’t! Get the helicopter out of here!” 

Pearson said nothing. It was a standoff, and all it would take was for the helicopter to open fire again, and the flyer would destroy it--and then the rest of them on the ground. 

Suddenly the noise from the flyer’s helmet evaporated, and the flyer turned away from the helicopter. 

“Look!” Petra shouted. 

She wasn’t pointing into the air, but at the smoldering cryptogen ship on the field. From the hatch a second creature was emerging. At first it looked so much like a human astronaut that it took Anaya a moment to realize the creature was wearing a synthetic white skin that covered almost its entire body. 

From the hood protruded a furred face that tapered into a long muzzle. Fitted across its large nostrils was a breathing mask, with tubing that fed into a slim pack on its back. Earth air wasn’t right for these cryptogens, not yet. The creature stood tall on its two powerful legs, then took a step across the field toward Anaya. 

In her mind, she saw a flare of familiar amber light, smelled damp soil--and instantly felt a flood of recognition, and relief. This was the person whose voice had filled her head so many times over the past days. And now here she was. Suddenly Anaya’s cheeks were damp with tears of relief. 

“It’s Terra!” she told everyone. 

“You’re sure?” Petra asked. 

Instinctively, Anaya was walking closer, to greet her. 

--You promised you would not attack! 

Terra’s silent words vibrated with bewilderment and hurt, but also anger. 

--I’m sorry! Anaya replied. It was one soldier, acting alone. We didn’t order it! 

She felt a stab of guilt that she’d been so quick to lose faith in Terra. Still, the sight of the flyer had been so shocking, so terrifying, what else could she think? 

“Keep your distance, Anaya,” she heard the colonel say. 

“It’s fine,” Anaya said. 

Nonetheless, she stopped a little distance away from Terra. The two of them regarded each other. Even in her white suit, Terra bore an uncanny resemblance to a kangaroo. A kangaroo without a tail. Her thighs were massive, and the lower half of her legs very skinny, almost bonelike. Long toes stuck through the synthetic white skin, and Anaya took in the wickedly sharp black claws--they made her own look puny. 

--Are we safe? Terra asked her. 

“Anaya, are you talking to them?” Pearson bellowed. 

“They want to know if they’re safe! You should get the helicopter to land!” 

“Not with that flyer still airborne!” 

--Why is there a flyer? Anaya asked Terra. You didn’t tell me there was a flyer! 

--He is a rebel, like us. 

Was it a lie? But as always, everything that passed into her head from Terra felt like the truth. She took a big breath and turned to Pearson. 

“The flyer’s a rebel, too. It’s safe!” 

Anaya couldn’t make out Pearson’s expression, but she guessed it was annoyance. Nonetheless, he spoke into his radio and said, “Stand down.” 

Immediately, the helicopter tilted and headed back to Deadman’s Island. 

--You’re safe, Anaya told Terra, and saw her shiver. Are you cold? 

The sky had darkened with clouds, and Anaya smelled rain. But with her own thick hair, she was still perfectly warm, sometimes too warm, now that it was summer. 

--Your atmosphere is cold, for us. These skins help keep us warm. 

As always, Anaya understood more than just Terra’s individual words. Skins meant the white fabric she wore. It was some kind of microfiber that regulated her body temperature. After so many early, clumsy conversations with Terra, the two of them had somehow forged a common mental language, like a forest path that got easier the more it was walked. 

Terra made a sound that Anaya realized was a sneeze. 

--Are you sick? Anaya asked worriedly. 

--Allergic. 

Of course! Terra had the same kind of allergies Anaya had suffered from all her life. It was strange, imagining the cryptogens having weaknesses, but this was not their world. Not their air, or sun, or pollen. 

--Where is the third rebel? Anaya asked. 

--There. 

And as Anaya watched, another cryptogen emerged from the ship.

Petra hated it instantly. 

It walked on all fours. The head that jutted from its weird white bodysuit was long and sloping, like an alligator’s. Maybe a dolphin’s--if she was being super kind. Its eyes were set way back. She couldn’t see ears. Its feet had long webbed toes. From its rear end curled a long tail. When its mouth opened, Petra saw sharp teeth. 

Like the runner cryptogen, the swimmer had a mask fixed over its nostrils, which were slit-like holes in front of its eyes. When its gaze locked with hers, Petra looked away. She didn’t want to talk to it. She was scared its words would appear inside her head. 

When the missile had hit the cryptogens’ ship, she’d been shocked, but hopeful, too. She wanted them destroyed. And then when she saw the flyer--she feared that she and all her friends had been lured here to die. 

She still felt far from safe. Her eyes darted between the three cryptogen species. She remembered those pictures in Seth’s sketchbook, the ones he’d shown them long ago. His dream creatures from another world. She’d hated them then. But seeing the real things now, right in front of her--that was a different thing altogether. 

She caught herself stepping backward. 

She shared half her DNA with these things. 

She didn’t want to look at them. She didn’t want to be like them. 

Was this what awaited her? 

The webbed feet. Walking on all fours. 

Would her body one day flip down to the ground? And she’d scuttle around, trying to hide her sharp teeth? 

Every muscle in her body was telling her to run. She felt a light pattering of raindrops on her bare arms and hurriedly brushed them off, knowing they’d start her itching. To her surprise, she caught the swimmer doing exactly the same thing, rubbing its face, swishing its tail against the earth to dry it.

“It has the same water allergy as me!” she told Dr. Weber. 

“We need to get them all inside the biodome,” Dr. Weber replied. “Anaya, can you explain to Terra?”

Awe: Seth wasn’t sure he’d ever properly experienced it before now. 

In the light rain he watched the flyer swoop down and land nimbly beside the other two cryptogens, its massive feathers folding back along its arms. It was the tallest of the three by far. Its broad shoulders and deep chest tapered to a slim waist and skeletal legs, also feathered, that ended in clawed feet. Seth saw the talons flex, gouging the ground. 

The talons startled him. They made the flyer seem even wilder than he’d imagined in his drawings. Power emanated from the flyer, and incredible danger, too. Heart pounding, Seth couldn’t stop staring. He got the sense that he was being examined, too. His own wings felt shabby compared to the spectacular golden spans of the flyer. He hadn’t seen its head yet, and waited, breathless, for the flyer to remove its helmet. 

With both clawed hands, the flyer gripped its helmet on either side and pulled it smoothly off. 

In his sketches, Seth had sometimes given his flying creatures the heads of humans, sometimes the heads of birds. But the reality was something altogether different. 

The eyes were large and dark, though there was definitely a hawklike intensity in them, and in the upswept angles of its brows. It was hard to tell if it had hair or downy feathers, but there were certainly silver and gold feathers in the amazing crest that rose like a crown from the back of its head. 

It had no mouth. 

It had, instead, a beak. Its tip had a downward hook and was wickedly sharp. 

Like the other cryptogens, it wore a mask fitted over its round nostrils above the beak. 

Seth longed to talk to it, and at the same moment, was terrified by the idea. Words abruptly seared the inside of his skull. 

--You’ve damaged our ship. 

--That wasn’t supposed to happen, he replied. 

Silence. Seth wasn’t sure he was believed. He could feel the energy of this creature, like an unstable charge of electricity, ready to strike like lightning. He knew what the flyer could do with its mind, the destruction it could inflict. 

--Were any of you injured? Seth asked. 

--No. 

“Anaya,” Dr. Weber said. “Tell them what’s going to happen next.” 

Seth heard Anaya silently tell all three cryptogens about the place that had been prepared for them. The dome on the other side of the trees. It had the right air and water. The right plants, too. 

Seth followed the flyer’s gaze across the field to the biodome and sensed that the cryptogens were talking among themselves, blocking him out. Then the three of them went together to examine the damaged hull of their ship. 

“Tell them,” Pearson said to Seth, “that we’ll help repair it.” 

When Seth relayed this to the flyer, the reply was mocking. 

--You cannot repair it. Only we can. And if we fail, our battle may already have been lost. 

Chapter Two

Petra was grateful for the windowless walls around her. She needed walls. Something to put between herself and everything that had just happened outside. Walls were good. Walls were normal.

On the field, she’d watched as the cryptogens were escorted inside an armored personnel carrier and driven to the biodome. She and Seth and Anaya had followed in a jeep. Inside the building, Petra was relieved they hadn’t been taken to the observation level. Instead Dr. Weber led them downstairs to a conference room in the warren of unfinished offices. She told them to wait there and unwind, then disappeared to join Colonel Pearson. 

Unwind? 

Petra went straight to the bathroom and locked herself in a stall. More walls. Dr. Weber had given her a pack of hypoallergenic wipes, and she started scrubbing her face. 

Outside, just before the cryptogen ship landed, they’d been attacked by a huge rhino thing with tentacles and a cratered mouth. And a tongue. A very long, yellow, sticky tongue that had dragged her by the head across the field. Her face still had tongue goo on it, and she was desperate to get off every last bit. 

She’d held it together when they fought and killed the rhino thing, when the spaceship landed, and when the three cryptogens emerged. That was a long time to hold it together, and now her whole body began to tremble. 

She’d had weeks to get used to cryptogenic plants and bugs, and after all that, you’d think nothing would shock her. But the real cryptogens made her feel like the entire world was flying apart. They were like people, despite their wings and claws and beaks. They were intelligent--more intelligent than humans, or how could they cross the galaxy to get here? 

Now that she’d finally laid eyes on them, there was no way she could trick herself into thinking they didn’t exist. They were real and the entire world was different now--and maybe coming to an end. 

She could practically hear her panic echoing around the bathroom stall, so she opened the door and walked out. She stood in front of the sink, thinking she might throw up, and took ten deep breaths. 

When she returned to the conference room, Anaya was perched on the table, Seth was pacing, and they were talking telepathically. Petra was instantly barraged by their conversation. They were going fast, talking over each other, like they had to get out all their words before they ran out of breath. 

--When it flew out of the ship-- 

--didn’t know what it was. That helmet--

--and the crest! 

--looked like a freaking angel, its wings-- 

--and the flyer’s voice, it was so-- 

--smoke and gasoline. Felt like I had bleeding lip--

--didn’t expect the legs to be so thin-- 

--confused by the white skin when I first saw Terra-- 

--who expects aliens to wear clothing, but I guess-- 

--it was like meeting, I don’t know, a different version of myself, Anaya said. 

--Yeah, agreed Seth. 

“Are you serious?” Petra said aloud. She had never been as good at telepathy as the others, and she definitely didn’t feel like using it now. “They’re aliens! Real aliens!” 

She sat down, trembling. Even her teeth were chattering. 

“Are you freaking out?” Seth asked. 

“Yes, I am freaking out!” 

“How can I help?” Anaya asked. 

“You can freak out, too! Why are you so calm?” 

“I’m not calm, believe me.” 

“Everything’s happened so quickly,” Petra said. “Oh my God, we really just met them!”

Seth sat down next to her and held her hand. All her attention went to her hand, his warm fingers wrapped around her icy ones. Some of her panic drained away. She didn’t understand how Seth could make her feel calmer so easily. But he did. He smelled bad, but she didn’t care.