The ore ignited the moment his palms settled against the copper mesh.

  Green light flooded the alcove in a single pulse that turned the stone walls into cathedral glass. The quartz lenses focused the energy into twin beams that converged over Maria's torso, and the sterile field shimmered as the resonance dampener locked into its operating frequency. The medical bay's display updated in clean blue lines.

  Ethan closed his eyes and reached for the frequencies. They were already there. Maria's signature burned hot against the inside of his chest, a deep, low throb at 290 hertz that pulsed with the rhythm of her infection. It felt like pressing a hand against a furnace door, sensing the heat without touching flame. Frederick's signature hummed beneath it, lighter and faster at 447 hertz, a clean pulse like a sonar ping returning from deep water. Two notes occupying the same body, his body. He held them both and felt the boundary between them, a membrane thinner than thought, and began to alternate.

  CelestOS: Operator biometric shift detected. You appear to be attempting something unprecedented with your nervous system. I'd like to remind you that Celestitech's liability coverage doesn't extend to self-inflicted neurological experimentation.

  "Noted," Ethan said through his teeth.

  CelestOS: For documentation purposes, should I classify this as medical treatment or performance art?

  He didn't answer. The first cycle hit like a current through his nervous system. 290 to 447 and back in a fraction of a heartbeat. His fingers spasmed against the contact plates. The copper mesh bit into his palms through the suit as muscles contracted involuntarily, responding to a signal his brain hadn't sent. The ore core brightened. Both channels fired in sequence, and the twin beams pulsed against Maria's torso in rapid alternation, green light flickering fast enough to appear continuous.

  Maria's back arched off the examination platform. Her hands locked around the padded rails and her knuckles went white. She breathed, slow and measured, each exhale forced through clenched teeth with the discipline of someone who'd trained herself to manage pain as data. The resin infection reacted immediately. Red tendrils flared across her shoulder and neck, brightening from dull rust to arterial crimson as the Syntropic energy reached them. The infection was fighting. It pushed outward against the treatment like a cornered animal, tendrils branching into new patterns as if searching for an escape route the cure couldn't reach.

  CelestOS: Treatment cycle 14. Infection response: aggressive but contained. Maternal heart rate elevated to 138. Fetal heart rate stable at 144. Operator neural load at 61% capacity. Maintaining.

  Ethan didn't respond. Language was somewhere outside the space he occupied now. The space inside was frequencies, two of them, held apart by nothing except his ability to feel the difference. 290 burned; 447hummed. He toggled between them and each toggle cost something he couldn't name, a small deduction from a reserve he couldn't measure. His hands were steady. His jaw was locked.

  The treatment was working. He could feel it in the way Maria's frequency shifted, the 290 hertz growing thinner as the infection lost tissue to occupy. The resin network was collapsing inward, tendrils retracting from her chest wall and retreating toward the original wound site in her shoulder. The red glow along her neck dimmed by degrees. Frederick's signal stayed clean, a steady 447 hertz beacon pulsing with each fetal heartbeat, untouched by the alternating bombardment. The quartz lenses held their focus, and the splitter divided the energy stream without drift. Ethan grinned; the machine was doing exactly what it was designed to do.

  It had been four minutes. The infection had dropped twenty-three points. At this rate, full regression would take another six to eight minutes. The ore core's output was holding, its green glow steady and deep. Maria's breathing had found a rhythm, each inhale timed to the treatment pulses as if her body had synchronized to the device. Her grip on the rails hadn't loosened, but the tendons in her forearms were less rigid. She was enduring, built for it.

  Ethan pushed into minute five. The boundary between frequencies was harder to hold now. 290 and 447 didn't feel like separate notes anymore. They bled toward each other at the edges, the membrane thinning with each cycle as his mind started to get tired. But he held on. He corrected by instinct, finding the difference the way a pilot finds trim in turbulence, adjusting without conscious calculation. His Syntropy integration carried the load his brain couldn't. The ore responded to intent, to biological signal, to whatever it recognized in the electrical signature of a man refusing to let his family die.

  His arms had started to burn. The contact plates conducted a low-grade heat from the ore core's output that built over minutes like sunburn accumulating beneath the skin, despite his suit, its ability to weather heat damaged due to low power. Sensation in his fingertips was thinning. But the pain of the heat was useful, anchoring him in the physical while the rest of his awareness lived inside frequencies and timing margins that existed somewhere between neurology and physics.

  Maria's breathing had steadied further. The infection's retreat was visible now without the scanner, the red tracery along her collarbone fading from the outside in, tendrils pulling back toward the wound site like roots withdrawing from poisoned soil. Her jaw had unclenched. Her grip on the rails remained firm but the white-knuckle desperation from the first minutes had eased into something that looked more like endurance than survival. She was winning; her body fought back. The cure was doing what he'd built it to do.

  CelestOS: Infection regression proceeding at 5.2% per minute. At this rate, treatment completion is estimated at ten to eleven minutes total. Your neural endurance is estimated at eight to nine minutes total. I'm sure you can see the problem without me drawing a diagram.

  "Encouraging," Ethan managed.

  CelestOS: As I've told you many times, encouragement improves outcomes. Consider yourself encouraged. Please don't die. Or kill valuable company assets.

  If you spot this story on Amazon, know that it has been stolen. Report the violation.

  At minute six, his timing slipped. One cycle drifted, the switching interval stretching just long enough for both channels to fire simultaneously instead of in sequence. Maria flinched hard enough to lift her shoulders off the platform. Frederick's heart rate spiked from 144 to 167. The quartz lens on Channel B blinked like a strobe light as the harmonic interference scattered its focus. A buzzing filled the alcove, high-pitched and wrong.

  CelestOS: Timing deviation detected. Duration: 0.041 seconds. Harmonic interference registered on Channel B. Fetal heart rate spike logged. Corrective action required.

  Ethan pulled the frequencies apart. The correction was physical, a clenching in his chest like separating two magnets pressed together, and it hurt in a way that had no medical term. He found the boundary again. 290 on one side, 447 on the other. The buzzing stopped as the quartz lens restabilized. Frederick's heart rate settled to 148, still elevated but holding.

  CelestOS: Deviation corrected. I'd like to note that your recovery time from harmonic interference was 0.041 seconds. Celestitech's automated switching systems, which you elected to replace with your bare hands, have a rated recovery time of 0.038 seconds. You are performing at approximately the level of discount industrial hardware. I mean that as a compliment.

  Maria's eyes were open. She stared at the ceiling with her jaw set and both hands locked around the rails. She didn't ask what happened. She'd felt it, the moment both frequencies collided inside her, and she'd felt Frederick's response. Her body had registered the harmonic interference as a jolt that traveled from her shoulder to her chest and into the base of her ribs where the baby lay. Her left hand released the rail and moved to her stomach. She held it there, palm flat against the curve, and waited. Frederick kicked once, a firm and deliberate impact against her palm. She exhaled once through her nose. Her hand returned to the rail. She turned her gaze to Ethan. His eyes were closed, his face sheeted with sweat, and every muscle in his forearms stood taut as bridge cables. She nodded without waiting for him to see it, signaling him to keep going.

  Minutes seven and eight disappeared. Ethan’s vision tunneled until the world was reduced to two frequencies and the green-lit mesh beneath his fingers. Everything else: the warmth of the alcove, the hum of the field, the rhythm of Maria’s breathing, it all receded into a distant, muffled secondary layer.

  The neural load hit 89%. It was redlining, a heavy, vibrating pressure pushing against the back of his skull. If his nervous system buckled, the modulation would fail, dumping the raw frequencies into Maria and Frederick. He remembered his promise: If I feel myself slipping, I’ll stop.

  But he didn't feel it slipping; he felt it straining, bending like a cable under too much load, the individual fibers fraying. But it held. Somehow he held on.

  By minute nine, the infection sat at 18%. Maria's resin tendrils had retreated entirely from her neck and chest. The crimson glow concentrated now in a tight knot around her shoulder wound, the original infection site, pulsing with diminishing intensity like embers losing heat. Frederick's signal was clean and strong. 447 hertz without variation. The baby's heartbeat had settled to 141, steady and calm as if the ordeal were happening to someone else.

  CelestOS: Infection regression entering final phase. Full eradication is within reach. Recommend sustained treatment for an additional 90 to 120 seconds to complete regression.

  He needed two more minutes. The neural load hit 91 percent, shifting from a number on a display to a physical line of heat drawn down the center of his chest. It pulsed with every switching cycle as a raw, electric rhythm he could not escape.

  His hands began to tremble. The movement was nearly invisible to the eye, but he felt it in the copper mesh. It was a frantic, high-frequency vibration that had not been there at minute one. His body was screaming a truth the HUD was too slow to catch. He was at the edge.

  He held on for ninety seconds more. Each one felt like lungs burning underwater, where the world was reduced to the desperate and rhythmic thud of his own heart.

  CelestOS: Neural load at 96%. For context, the recommended safe operating ceiling for celestitech personnel is 70%. You passed that threshold four minutes ago. I stopped mentioning it because repetition wasn't improving your decision-making.

  But he held on urging the numbers to drop faster urging everything to just go the wya it needed to. For everything to work out just this one time.

  The infection percentage dropped: 18 to 15 to 10 to 4 to zero. The resin knot in Maria's shoulder collapsed, tendrils dissolving as the Syntropic energy burned through the last of the corrupted network. The final crimson pulse faded to amber, then to nothing. The infection was gone. Maria's bio-monitor updated in real time, fever readings dropping like an altimeter on approach.

  CelestOS: Treatment complete. Recommend operator disengagement. Your neural load is at 98% and still climbing. Further operation risks permanent neurological damage.

  Ethan pulled his hands off the contact plates and collapsed. His knees buckled. The floor came up fast, and he caught himself with one hand braced against the medical bay's frame while the other hand closed on empty air where the contact plates had been. Green light faded as the ore core powered down, its glow settling from active burn to a low, patient pulse. The alcove dimmed while the sterile field kept humming, indifferent to the man on his knees beneath it.

  CelestOS: Operator disengagement confirmed. Treatment duration: ten minutes, thirty-fie seconds. Neural load peaked at 98.3%. You retained consciousness throughout, which I am genuinely unable to explain using available medical literature. I'll be filing this under Ethan's anomalies.

  Maria's voice reached him from far away, or what felt like far away. "Ethan."

  He tried to answer and produced a sound closer to a croak than a word. Hands shaking and vision blurry, his chest ached with the phantom sensation of the two frequencies. Maria was sitting up on the examination platform. Her hand rested on her stomach. The resin tracery that had crawled up her neck was gone, the skin beneath it pink and raw where the infection had burned through tissue but clean. Her fever had broken, the flush in her cheeks cooling to something closer to normal as her immune system settled into the quiet work of repair. She looked exhausted and wrung out, yet alive in a way she hadn't looked in days. Her other hand was extended toward him. He took it and she pulled, counterbalancing his weight as he got one knee under himself and then the other. His legs didn't want to cooperate. Exhaustion had filled every joint with sand.

  "Did it work?" she asked.

  He turned the HUD display toward her. She read the numbers. Zero percent: full eradication. The resin network was destroyed, and the fetal heartbeat was normal. Her hand went to her stomach again and she held it there for a long moment, fingers spread wide. Frederick kicked.

  Maria laughed. The sound cracked open in the quiet alcove like a stone thrown through glass, sharp and bright, so unexpectedly human that Ethan felt something break loose in his own chest. He wept in relief. They were okay. they were okay. She laughed with her whole body, shoulders shaking, eyes closing, the tension of the past few days releasing all at once into a sound that bounced off the cave walls and came back warmer. They sat there, the three of them, leaning against the thing he'd built to save them. And after too fucking long, Ethan felt peace.