A shriek from the windows behind them made Josie and Nick turn. In the darkness of the other two cells, she could just see a swirling of movement, a chaos of wings and bodies nebulous in the shadowy night.

"My army," Mr. Byrne said with a nod toward the window. "I've promised them fresh meat."

Nick sucked in a breath. "You communicate with them?"

Mr. Byrne laughed again, but this time with genuine enjoyment. "Oh yes. Our research is quite advanced. The Nox are significantly more sentient than we give them credit for. More like a dolphin than a dog in their ability to intuit our intentions. As soon as they discovered that we could come to a mutually beneficial arrangement, they naturally got on board."

Nick tilted his head. "Mutually beneficial arrangement?"

"Of course. We have to work together, you know. They provide certain services to the Grid as required. Like your little friend. And I make sure they are healthy, prosperous"-he paused and shrugged-"and plentiful."

The intensity of the shrieking increased, almost as if the Nox were getting impatient. Something bumped against one of the windows. Then another, harder. The Nox were trying to get out. Josie remembered the way they'd come tearing into the warehouse-a fierce, merciless attack-and shuddered.

Mr. Byrne pressed another button on the wall and this time Josie heard the sounds of two deadbolts being thrown. Her stomach flip-flopped. He'd just unlocked the two doors behind them. "Now the lights are the only things keeping them at bay. So I suppose the choice is yours. You can play nice and I'll make sure to kill you both quickly and cleanly before I let them in. Or not, and I'll shoot you both in the kneecaps, feed you to the Nox, and pick through your bones."

Josie glanced around the lab, desperate for a means of escape. Bare tables, dormant lab equipment, a desk, some chairs. Her eyes drifted upward to the overhead light illuminating the room, its humming made dormant by the shrill cries of the Nox behind them. It was a single, massive fluorescent bulb that ran practically the length of the room. But just one, and it was the only light in the lab.

Josie bit her lip. They'd come so far, were so close to the finish line. Her mom, Jo, Penelope, not to mention the entire human population of both their worlds-so many people were counting on her. She couldn't let them down. Not if she could help it.

That night in the forest, the Nox hadn't directly attacked her-more like accidentally found her in the darkness when she cried for help. And in the warehouse, when Nick had been the focus of the attack, the Nox barely touched her-even seemed surprised and scared when she lashed out at one. It was as if they didn't know she was there.

Like she wasn't in their world at all.

It was a hypothesis only. A theory developed from a logical examination of the facts. But Josie was about to bet her life-and Nick's-that she was right.

"Well?" Mr. Byrne said.

Nick squeezed Josie's hand and turned to face her. His eyes were sad, defeated. "I'm sorry," he whispered.

Josie smiled. "We're not dead yet."

Nick's brows drew together with a question he never got a chance to ask. Without warning, Josie spun around, grabbed a Bunsen burner off the table, and heaved it at the overhead light.

"No!" Mr. Byrne screamed.

Nick gasped. "What are you doing?"

For an instant, nothing moved. The burner seemed to hang in midair, locked onto the long fluorescent bulb above them. There was no sound, just a frantic blinking that happened in slow motion as the fixture swung violently back and forth on its moorings. Josie held her breath. She wasn't sure if she wanted the light to go dark or not. If she was wrong, she and Nick were in for a horrific death. But at least they'd be taking Mr. Byrne with them.

The room went dark for a split second and Josie heard repeated thuds as the Nox propelled themselves against the cell doors. The light blinked back on, bathing the room with its sterile blue-white glow for a half second, then with a crack that Josie could feel more than hear, the bulb broke free of the fixture and plummeted to the ground, submerging the room in total darkness.

Without warning, life kicked into regular speed. She grabbed Nick by the arms and pulled him to the ground just as the muzzle of the gun flashed. But Mr. Byrne and his handgun were the least of her problems.

The sound of a crash pierced the room and suddenly the shrieks of the Nox were twice as loud. Josie felt the rush of air as they swooped into the lab.

Nick wrapped his arms around her to try and shield her from the Nox, but this wasn't the time for chivalry. "Curl up into a ball," she whispered.

"What? Why?"

"Stay quiet." She didn't have time to explain. "Trust me."

Without waiting for him to comply, Josie forced him onto his side, then climbed on top. She wrapped her arms tightly around him, resting her head directly on top of his. Maybe, just maybe, they wouldn't be able to sense Nick with her covering him.

A scream tore through the chaos. Not an animal this time-human. It was close to them, just on the other side of the table, and Josie could feel the terror of it seeping into her bones.

"No!" Mr. Byrne cried. "Not me. Not me!"

His screams shifted, less pleading and more pain. Excruciating pain, the kind of cries Josie imagined from a fourteenth-century witch burning at the stake. The air beat around her, faster and faster, a torrent of ecstasy in the kill.

Josie hugged Nick tighter. So far she hadn't felt as much as a wing graze her body as they lay on the floor in some kind of bizarre spooning pose.

Suddenly, Mr. Byrne's screams choked off. There was an abatement in the shrieks of the Nox, and Josie could hear sputtering, like a man drowning. She heard a crash, and felt the reverberations through the floor. A table falling over as Mr. Byrne made one last, desperate attempt for the door.

Without warning, the Nox exploded into a frenzy. The noise of their screaming was so loud Josie was sure her ears were bleeding. But she didn't move her hands to her ears to try to mute the noise; she kept them wrapped around Nick. She had to protect him. The screeching intensified, at once joyful and horrific, and Josie realized it was the bloodlust as they ripped Mr. Byrne's body to pieces. The table bounced, pushing up against them from one side, and Josie could feel the vibrations of the Nox as they attacked Mr. Byrne's body again and again and again. . . .

Then as suddenly as it began, the room went silent.

Josie didn't move. Her head throbbed, her ears rang from the sheer decibels of the noise that had inexplicably ceased, and her breaths came fast and deep, like after line sprints in PE. Beneath her, Nick didn't stir. She could feel him breathing just as heavily as she was, but neither of them felt brave enough to move.

Nick was the first to break the spell. "I think they're gone."

"Where?" Josie whispered.

"Wherever they go during the daylight?"

Josie nodded, even though Nick couldn't see her in the darkness. "They must have phase shifted. Like Tony said."

"What happened?" Nick asked breathlessly. "I mean, why aren't we dead?"

Josie continued to straddle him. "I think . . ." Her voice was trembling. "I think it's like with Tony, where he's not quite in our world but not quite out of it? I think that's what's happened with me. When I came through the portal."

Nick shifted, and she sat back on her heels, freeing him from the weight of her body. In the pitch darkness, she didn't realize he was sitting up until his nose grazed her cheek.

Nick froze, and Josie heard him suck in a quick breath, then slowly he drew his cheek against her own. His skin was rough with stubble. It scratched her face, but Josie didn't care. She inhaled deeply and caught the spicy traces of aftershave long since applied. She wanted to bury her face in his neck and take gulping breaths of him.

Fingers against her face. Just the tips, deliberately outlining her jaw, the contours of her face. Nick's touch was soft, yet assertive. She could sense his want, his need to touch and feel her, but with a gentleness that Josie had never encountered in his predecessor. His fingertips traced down her cheeks to her chin, and his thumb swept lightly across her lips, causing a fluttering thrill deep within her.

Josie's heart thundered in her chest. She reached a tentative hand forward and pressed it against Nick's body. Through the thin cotton of his shirt, she could feel the strong, rapid beat of his heart. He was just as excited as she was.

Her touch gave Nick the green light. His hand snaked behind her neck and pulled her to him. The feel of his lips against hers was electric.

Josie pressed her mouth to Nick's and kissed him greedily. She'd fantasized about this moment so many times, but it had never been like this. In her dreams, she was using him as a substitute for the boy who had broken her heart. But that pain and loss had passed, and now Josie found herself yearning for this Nick of his own merit. He was not her ex-boyfriend. He was different. He was better.

And she was in love with him.

Nick moaned softly into her mouth as he wrapped both of his arms around her. He rolled over, cradling her head in his hand so she wouldn't clonk it on the tile floor, and slid his body on top of hers. She arched her back as she deepened their kiss. The darkness that had been a thing to be feared, a place where nightmares lived, had lost its menace. Josie couldn't see the outline of Nick's face and body, though they were just inches from her own. She couldn't tell where his hands were, where he would touch her next.

Nick gently glided his hand up beneath her shirt, then kissed the soft part of her neck just below her ear. Josie trembled as he inched his hands upward toward her chest. So slowly it was almost torture. Her body ached for him in a way she'd never felt before. She wanted to feel his hands on every inch of her skin, to revel in the warmth of his body sliding against her own. Just as his hand swept over her breast, she reached her arms up over her head.

Her hand touched something in the darkness.

A shoe.

Josie pulled her lips away from his; the spell of Nick was broken in an instant.

"What's wrong?" Nick panted.

Josie didn't answer. She felt up the smooth, leather of the shoe to a sock. A sock clothing the hard bone of an ankle. A sock that was sticky and damp.

She yanked her hand away, realizing what it was, but the foot came with her, sliding several inches closer to where she lay on the floor. It was easy and light, as if it was no longer attached to a body.

"Oh my God!" Josie pushed herself up, cracking her forehead against Nick's in the process. Nick grunted, fell back, and Josie scrambled after him, desperate to get away from the body on the floor.

"Are you okay?" Nick said, reaching for her in the darkness.

"It's . . . it's . . . ," she started. Her brain felt paralyzed and all she wanted to do was wash the hand that had accidentally touched Mr. Byrne's severed leg.

"Oh my God."

Nick rocketed to his feet and fumbled around in the darkness, swearing under his breath as he bumped into tables and crunched on broken glass in his sneakers. After a few seconds, she saw the weak but steady beam of the flashlight a moment before Nick shined it in her face. "Are you okay?" he asked again.

Her face must have answered when her voice couldn't. Nick sprinted to her side and lifted her to her feet. She felt his strong arm around her waist, and she let her body sag into it. But she couldn't enjoy the sensation, not even for a moment. The beam of Nick's flashlight traced a slow trail across the lab floor, sweeping back and forth, looking for the remains of Mr. Byrne. He spotted the shoe first, black and unmarred, as if its owner had just come from a shoeshine.

Knowing Mr. Byrne, he probably had.

As Nick traced the shoe up to the ankle and beyond, Josie saw what she'd feared: the leg was severed at the knee. Shreds of the dark dress slacks Mr. Byrne had been wearing still clung to the leg, gathered down by the blood-soaked ankle. But the rest of what had been his lower leg was little more than a skeleton. Thick puddles of blood spilled out in every direction, splattered across the floor by the frenzy of the attack. Bits of ripped and shredded flesh still clung to the bones, but for the most part, the Nox had picked it dry.

Josie couldn't help but wonder how long he'd remained conscious during the attack. Judging by the horrific screams she'd heard above the clamor of his attackers, it was long enough.

His army. His allies. Only so far as he could control them. In the end, he was just another meal.

Nick turned Josie around and raised his flashlight beam to the wall. "We don't need to see any more."

FIFTY-FOUR.

7:06 A.M.

JOSIE FOLLOWED NICK AS THEY RACED DOWN the hall. He kept his gun, retrieved from beside the body of Mr. Byrne, poised, expecting to see a security guard at any moment. People would be arriving for work, which would hopefully provide a distraction of some kind as they tried to get their friends out of the building.

Nick barreled into the stairwell, Josie close behind him.

"She said there was a lab on the third floor and that's where they'd be."

Nick glanced back at her. "Who said that?"

Oh yeah, she'd forgotten to mention that part. "I brought Jo back with me."

Nick screeched to a halt at the third-floor landing. "You trusted Jo Byrne."

"Yeah."

"After everything she did to you?"

It sounded like such a bad idea when he said it like that. "I didn't have a choice."

"Shit." Nick checked the gun cartridge, then cocked the barrel. "How many times do I have to tell you, you can't trust her?"

Just then, the door to the third floor flew open and Jo Byrne popped into the stairwell. "Can't trust who?" she said with a huge smile.

Nick vaulted back, holding his gun out in front of him. "Where are they?" he barked. "Where are my friends?"

"It's okay, Nicky." A shadow slid into the stairwell and Josie recognized the raspy voice of Tony Fiorino. "It's all good."

Madison followed him. "Tony slipped out of the lab when Mr. Byrne brought Jo in."

Tony laughed. "Easy when you're a shadow."

Zeke and Zeb were the next through the door. "He got the keys," one of them said.

"From Dr. Cho," said the other.

Jo smiled. "And here we are."

Jackson slipped into the stairwell last. He carried a thin figure in his arms. She was wrapped in a blanket and her dark hair hung over her face.

Josie's voice cracked. "Mom?"

"I'm okay," her mom said weakly. "I'm going to be okay."

Josie turned to Jo, grabbed her by the shoulders, and hugged her. "Thank you."

3:50 P.M.

"Do you think your mom will agree to come back now?" Josie asked.

Jo laughed. "With Daddy gone? Yeah, she'll be cool."

Josie smiled.

"I really am sorry," Jo said simply. "About everything."