Chapter 17
Seventeen
The exhaust port was a wound in the volcanic rock, barely wide enough for a person to fit through sideways. It breathed heat in slow, wet pulses, like something alive and sick.
Grace pressed herself flat against the basalt beside it, her cheek against stone still warm from the last thermal cycle, and watched Gunnar clip his rappelling line to the anchor bolt Astryde had drilled into the rock face. The air coming out of the vent smelled like sulfur and hot metal.
“Sixty feet,” Astryde said, feeding rope through her belay device. “The mechanical level is at the bottom. Watch the outcropping at thirty where the basalt narrows.”
One by one, they dropped into the dark. Gunnar first. Then Magnus. Then Astryde.
Then it was Grace’s turn.
She clipped in, tested the line, and leaned backward off the edge with a shaky exhale.
“You’ve got this,” Tiikaan mumbled, and her gaze jerked up from the vent at the encouraging words.
“Trust the gear.” He made a show of checking her harness. “You’re good.”
He winked, and a half-laugh rushed out before she could stop it.
“Thanks.” She took one more deep breath, then stepped backward into pitch black.
The descent was nothing like hacking. Hacking was control. In the digital world, she dictated the pace, the angle of attack, and the terms of engagement. Here, she was at the mercy of gravity, friction, and absolute darkness.
The rough bite of the rope through gloves she hadn’t worn enough to trust was her only tether. If she slipped, if the gear failed, there was no undo command. She only stepped backward off that ledge because she trusted the Rebels wouldn’t let each other fall.
The basalt walls pressed close on both sides, slick with mineral condensation, and the heat rose around her like a sick, living thing.
Her terminal bumped against her hip with every step down, and she prayed it wouldn’t bump into stone and break.
It was the only piece of this nightmare she understood.
Thirty feet. The outcropping Astryde had warned about forced her sideways, her shoulder scraping against rock. Panic flared, hot and bright, as she felt the vest catch and pull. She fought the instinct to scramble, hanging suspended in the suffocating heat until the fabric released.
Sixty feet. Her boots hit metal grating, and the world opened up.
The mechanical level was cavernous and dark, broken only by the dull red glow of emergency lighting along the floor. Pipes ran along the ceiling in thick bundles, sweating condensation that dripped onto the grating in an uneven rhythm.
The air was cooler here but recycled and stale, tasting faintly of machine oil and ozone. The hum of generators vibrated through the floor and up through her boots, a low, constant frequency she could feel in her teeth.
The team was already in position. Gunnar and Bj?rn had taken point, weapons up, scanning the corridor ahead. Astryde covered the rear.
Magnus stood right beside her as he unhooked her from the ropes. Not touching, but close enough that she could feel the warmth of him through two layers of Kevlar.
“You good?” he asked, low enough that it didn’t carry.
She stepped away from the ropes. “I’m good.”
She wasn’t. Her hands had a fine tremor she couldn’t will away, and her heart was doing something irregular and unhelpful against her ribs.
Grace unclipped her terminal from her belt and powered it on.
The screen cast a pale blue glow across her hands, and she watched the boot sequence with the same focus she’d given every hostile terminal she’d ever sat down at.
One missed log, one stray process, and whoever owned the system knew you were inside.
The terminal went live, the connection to Rafe’s overwatch channel was solid, and the facility’s internal network was right there. She could feel it, almost, the way you could feel the static charge in the air before a lightning strike.
“Rafe,” she said into her earpiece. “We’re on the mechanical level. Starting the first breach.”
“Copy, Ghost.” Rafe’s voice was steady from Colorado, the tap of his keyboard audible underneath. “External perimeter is clean. No alerts triggered. You’re invisible.”
Grace crouched against the base of the corridor wall, her back to the cold metal, and opened the first of the three firewalls standing between them and the vault. The terminal balanced on her knees. Her fingers found the keys.
She’d built this system. Not all of it. Patroclus had its own engineering team, military contractors with clearances she’d never held. But the adaptive layer, the one that learned from intrusion attempts and rewrote its own defense protocols in real time — that was hers.
Lars had sold it to the DOD through three shell companies, and nobody in the Pentagon had any idea the architect was a nineteen-year-old working out of one of his mobile server farms — a shipping container at the Port of Rotterdam, packed with racks he could load onto a freighter and disappear if anyone got too close.
That was the project where she’d finally seen him. A man who kept his empire packed for flight didn’t believe in any of it. Not the contracts. Not her. She’d built it anyway. By then, she’d been too deep to walk away.
Now she had to unmake it.
“Moving,” Gunnar said from ahead, his voice clipped. “First corridor is clear.”
The team advanced. Grace moved with them, walking and typing simultaneously, her eyes splitting between the terminal and the dark corridor ahead.
Magnus stayed close, a steady weight at her periphery that her nervous system had started treating as permanent, the way the body adjusts to the hum of a generator and stops hearing it.
Except she hadn’t stopped hearing him. She heard every breath.
The first checkpoint was a biometric scanner embedded in a reinforced door. Military-grade, designed to read retinal patterns and palm geometry simultaneously. Grace had designed the authentication algorithm.
She also knew the back door.
The team formed up around her while she worked. Nobody spoke. The only sounds were Grace’s keystrokes, the drip of condensation, and the low hum that never stopped.
The authentication prompt dissolved. The door’s magnetic lock released with a heavy, satisfying thunk.
“First checkpoint,” Grace whispered. “Through.”
They moved into sub-level two. The corridor narrowed.
The emergency lighting shifted from red to amber, and the air got warmer, with an undercurrent of something chemical that burned the back of Grace’s throat.
The generators were louder here, close enough that the vibration came up through the walls as well as the floor.
“Patrol,” Tiikaan said, so quiet it was almost mouthed.
Everyone stopped. Grace killed her terminal’s screen with a single key and pressed herself flat against the corridor wall, blending into the shadows.
The cold metal bit through her vest. In the amber gloom, she could see shadows moving at the far end.
Two shapes, the silhouettes of Marines walking their rounds, rifles held across their chests.
Magnus shifted silently, stepping directly in front of her. Not touching, but close. Putting his mass entirely between her and the corridor.
The Marines’ boots echoed on the grating. Getting closer.
Grace held her breath. Held everything. The terminal was dark in her hands.
If the patrol turned, if one of them swept a flashlight across the shadows, Magnus would take the first bullets.
He was offering his life for hers, standing there with his weapon ready and his breathing so controlled she couldn’t even see his shoulders rise.
The footsteps passed. Faded.
Neither of them moved for three full seconds after the sound disappeared.
“Clear,” Tiikaan said.
Magnus let out a slow exhale and turned back to check on her. The brief flare of adrenaline started to recede, leaving Grace shivering slightly in the damp, circulated air.
She powered the terminal back on and kept moving.
“I’m losing you here, team.” Rafe came through the comms as they approached sub-level three. “After this point, you’re past my eyes. I’ll hold the perimeter from up the chain.”
The air changed again — colder now, drier, scrubbed by the environmental systems that protected the vault’s sensitive equipment. The amber lighting gave way to harsh, blue-white LEDs that made everyone’s face look like it had been carved from ice.
Grace was halfway through the second firewall when the facility woke up.
Not alarms. Nothing so obvious. The first sign was a low mechanical whine that hadn’t been there three seconds ago. Then the lights in the corridor ahead flickered a single, deliberate pulse. Like a blink.
Grace’s hands froze on her terminal.
She knew that sound. She’d programmed that sound. It was the adaptive defense layer shifting from passive monitoring to active threat assessment.
The system had detected them.
“Nobody move,” she said.
“Grace—” Gunnar started.
“Nobody move.”
Her fingers were already working, pulling up the defense layer’s status on her terminal.
The adaptive system was doing exactly what she’d designed it to do— isolating the anomaly, mapping the intrusion, and preparing a proportional response.
The problem was that “proportional response” in a military context meant something very different from a pop-up warning when hacking.
The corridor ahead of Gunnar sealed.
A blast door dropped from the ceiling with a pneumatic hiss that sounded obscenely calm for how fast it moved. One second, there was a corridor. The next, there was a solid wall of reinforced steel, and Gunnar was on the wrong side of it.
“Gunnar!” Astryde’s voice cracked through the corridor. She was at the door in two strides, palms flat against the steel. “Gunnar, respond!”
“I’m here. Sealed in. About twenty feet of corridor, blast door on both ends.” His voice came through the comms, taut but controlled. “And there’s a sentry turret warming up in the ceiling.”
Grace’s stomach dropped.