Anna woke early, opened her eyes and blinked, letting the pale morning light wake up her brain. Her arms were still folded across her chest, revolver resting against her breastbone. She shifted, her limbs aching. Her watch glowed as she raised her hand. It was around five o’clock. It wasn’t like she had the BBC to check the accuracy any longer.

Beside her, Julia snored softly, murmuring in her sleep, her rifle slotted in the small gap between her mattress and the side of the bunk. Anna rolled out of bed fully clothed, as she always was now. After yesterday’s exertion, she was sore. The graze on her cheek smarted, matching the tender bruised spots over most of her body, but she had no doubts it had been worth it. Her armour had been resistant to the Chittrix venom, and the pulse rifle had worked without fault. Now they were ready.

She slipped on the armoured jacket that lay on the chair beside her bed, pulling the side straps snug against her slim frame. She tugged her belt closed and hung the lanyard chain with her security access card round her neck. The chain jangled softly.

Julia groaned across the room. “Where the hell are you going at this ungodly hour?”

“I’m going down to check the radio, see if those military signals we identified are broadcasting again.”

Julia sat up, the thin blanket falling away from her curvy frame as she pushed unruly chestnut curls off her face. Half-Spanish and nearly forty with a penchant for corsets and vertiginous heels, Julia was the polar opposite of a typical scientist specialising in acoustic weaponry, a fact she had often used to her advantage in both her work and personal life.

Julia wagged a warning finger. “Make sure you don’t go upsetting Blake. He’s been hanging over that radio like a deranged mother hen the last couple of weeks,” she sighed. “I can’t get any sense out of him at all. I think the isolation is unhinging him.” She rubbed her cheeks in an effort to wake herself up. “It’s certainly getting to me.” She gestured at the functional room with its dented, bare walls. “If you’d told me I’d end up living in military quarters, I’d have laughed in your face.”

“It’s kept us safe.”

Julia nodded in agreement. “Yes, but not forever.” She swung her legs out of bed, dropping her bare feet to the floor and taking her glasses from the battered metal cabinet next to her bunk. Anna had embraced survivalist cargo trousers and t-shirts, but Julia had definitely not. She insisted on wearing lacy scraps of underwear beneath the utilitarian clothes that survival necessitated. Now she padded across to the small bedroom sink, fuchsia-pink knickers just visible under the hem of the sage-green, military issue t-shirt she wore. Drawing herself a glass of water, she peered over the edge of her spectacles at Anna.

“I secured the Sweeper last night while you were faffing around cleaning that armour of yours. I added transportation restraints.”

Anna chucked a ball of socks across the room at her. “That armour will save your life one day.”

Julia ducked.

“Is it ready?”

Julia shrugged, her face serious. “As ready as it will ever be.”

She’d been refining her hypersonic bomb prototype for the past five years from an unwieldy, bulky unit that required a heavy vehicle to move it to a smaller, lightweight device that was portable and most importantly, usable.

“The range is limited. I’m still banging my head on the table on how to increase reach without losing power,” she sighed. “I’m beginning to wonder if it’s even possible.”

Anna’s tone was dismissive. “You’ll figure something out. You always do.”

Julia snorted and pushed her glasses high up on her hair. “I’m going to dress. I’ll catch up with you shortly.”

* * *

Dim grey light filtered in through the slotted skylights as Anna walked along the hallway. She knocked softly on Blake’s door. No reply. She pressed an ear to the door, but there was nothing. Asleep? Her hand rested for a moment on the door handle. Blake was a privacy freak, even more so in the last few weeks, and he went mental if she opened the door to his room without his permission. Besides, he was barely speaking to her after yesterday.

She stepped back from the door, letting it be this time. She had other fish to fry.

She turned and followed the corridor to the communications room. She pushed open the door, expecting it to be empty, but Blake was there, sitting in front of the radio.

He was holding the headphones pressed to his head, nodding gently as he listened. His good leg was tucked under the chair while his amputated stump rested on a spare stool, dried blood crusting the folded edges of his trousers. He’d lost his right leg at the beginning of the invasion, ironically under the wheels of a military vehicle, and it hadn’t healed well. Of course, he’d lost far more than that. A creased picture of his wife and son was taped to the wall, a reminder of happier times.

“Blake?” He didn’t respond. His eyes were scrunched shut in concentration. He’d been toiling for over a week on a project he wouldn’t share the details about.

Anna stepped into the room, letting the door swing shut behind her as she approached the desk. “Blake? What are you doing?” Tinny noise spilled from the headphones but the noise was undecipherable. She let her hand rest on his.

His eyes flew open at her touch. Uncomfortable under his scrutiny, Anna stuck her hand in her cargo-trouser pocket. Blake had made his intentions clear to her several weeks before, and she didn’t want to give him any idea she had changed her mind. Things were embarrassing enough between them.

He turned off the radio. The expression on his face was haunted.

Anna had the distinct sensation she had interrupted something. The silence in the room stretched between them. It was hot and stuffy, like everywhere else in the building. She longed to be in a room with an open window and soft air cooling her skin.

Blake blinked, his face changing, softening. A predatory smile flashed and then was gone.

I’m imagining things. I’ve been locked up here for too long.

“Any luck?” she asked. He had picked up some military-sounding communication a few days ago but hadn’t been able to find any more since.

Blake shook his head. “I’ve been trying all morning. Seems to be quiet.” He ran a hand through his hair. “They’re probably running on intermittent power like us. It’s impossible to predict when they are online.” He paused. “Of course, with things the way they are, they could be permanently gone, and we’d never know. It’s all just shooting in the dark. They may all be dead now.”

Anna huffed out a breath. “They sounded organised. Military. If we’re still here, there has to be others.”

“Possibly.” He looked unconvinced. His eyes were red with fatigue.

Anna realised she’d been holding her breath and let it go. He might not have forgiven her for yesterday’s stunt, but at least he was speaking to her.

Abruptly, another receiver behind them burst into life, a torrent of alien noise spewing from the speaker and filling the small room with harsh, guttural clicks and whistles. Anna’s stomach lurched. She still wasn’t used to the sound, even after all the hours she’d spent listening to it as Blake worked on deciphering the language.

Little progress had been made by world governments in communicating with the Chittrix, but Blake remained convinced it could happen. They just needed to keep trying. Previously, he had worked as a translator for the Ministry of Defence, liaising with foreign investors, smoothing the bumpy road to make it easier for them to get their wallets out. But he’d spent most of the last six months with his headphones on, listening to the clicks and rattles of the aliens as they swept across the world, annihilating everything and anyone that stood in their path.

Initially, he’d made good progress isolating common characters in their language, the closest he could approximate to vowels and consonants. He’d identified patterns that represented what he thought were specific commands based on what was happening in the world.

But about a month ago, he’d stopped finding new patterns. He spent days slouched in his room staring at the walls, and nothing Anna or Julia did made any difference to his behaviour. He barely ate, hardly acknowledging they were even there.

Then, after about ten days, he emerged from his crazy cocoon and began to speak to them again. He relocated his equipment up to the north end of the building, away from where Julia and Anna were working. He’d said the reception was better and slipped into a work coma where all he did was sit with his headphones on and his notepad in front of him, full of dark slashes and marks.

Anna reached forward and flipped the red off-switch, and the room descended into dusty silence once again.

“I thought we lost the alien frequency?”

“We did. It comes and goes.” His eyes slipped to the side, avoiding her scrutiny.

“Gives me the creeps.”

Blake shrugged. “Their communication is far more sophisticated than you give them credit for.”

He stood, shoving his chair back and reaching for the crutches he now used. One clattered to the floor. Anna picked it up and passed it over, her fingers grazing his. Their eyes locked at the touch. Anna snatched her fingers away, flushing. She blinked, clearing her thoughts of Blake, alien language, and communication with the outside world.

“I’m going to be in the lab with Julia today.”

Blake nodded but didn’t speak, picking up his worn notebook and securing it with a wide elastic band. He wedged it under his arm before limping from the room, the tips of his crutches squeaking on the rubberised floor. As soon as he left, Anna turned the volume on the radio down and then clicked it back on, picking up the headset and settling it over her ears.

She twisted the dial, spinning through a cacophony of alien shrieks and dark, gritty interference.

Nothing.

Just as he said.