Chapter 1: The Green Rock
The air in Lecture Hall B hummed with a different frequency than the others. It wasn’t just the baseline whir of the holographic projectors or the soft sigh of the climate control. To Kara Danvers, it was a low, planetary thrum, a vibration she felt in her molars—the residue of a Kryptonian power cell she’d secretly buried under the sub-flooring a year ago after a close call downtown. Its presence was a risk, but so was leaving unstable alien tech in a S.T.A.R. Labs dumpster.This way, she could keep an eye on it.
Today, the familiar hum was a grounding wire.She needed it.
“So, if you’re a really, really impatient star,” she said, pacing before the main display, a swirling hologram of a red giant, “you skip the carbon babysitter phase and just go straight to…”
She snapped her fingers. The hologram imploded, then exploded in a silent, breathtaking nebula of colors. A few students in the front row jerked back, then laughed nervously.“Boom.Supernova.Space confetti. The end.” Kara smiled, tapping her tablet to bring up the next slide. “Any questions on the Chandrasekhar limit before we…”
The heavy door at the top of the tiered seats clanged open.A student stumbled in, late, his backpack slung over one shoulder. Kara’s polite, professional smile was already forming—late students were common, her policy was grace—when her senses spiked.First, it was smell. A sharp, acrid tang, like ozone and crushed chrysanthemums, cut through the ordinary scents of old coffee, dry erase markers, and adolescent anxiety.Then, sound. A faint, high-pitched whine, just at the edge of human hearing.To her, it was a dentist’s drill directly into her spine.
Her eyes locked onto the source.
Marcus Chen, sophomore, astrophysics major, bright but notoriously unfocused, was clutching something in his right hand.A rock, roughly the size of a plum. It was dull, mossy green, and it pulsed with a faint, sickly light from within its crystalline structure.Kryptonite.Her stomach liquefied. A cold sweat bloomed instantly between her shoulder blades. For a second, the lecture hall tilted, the faces of her sixty students blurring into a meaningless watercolor. The primal part of her brain, the Kryptonian part drowned out by years of sunlight and diplomacy, screamed one single, chemical command: RUN.
She didn’t run.She breathed.In through the nose, out through the mouth.Human air.Earth air.
“Mr. Chen,” she said, and her voice was only a half-octave higher than normal. “Nice of you to join us.”
“Sorry, Professor Danvers,” Marcus mumbled, not looking sorry at all.His dark eyes were bright with a feverish curiosity. He shuffled down the aisle to an empty seat, but he didn’t put the rock away. He set it on the desk beside his notebook, where it continued its silent, malignant pulse.
Kara forced her gaze away, back to the hologram.The colorful nebula now seemed nauseating. “As I was saying.Supernova remnants. Who can tell me…”
She continued the lecture on autopilot.Her mouth formed the words about neutron stars and gravitational collapse.Her hand gestured at diagrams. But every atom of her being was fixed on that pulsing green rock thirty feet away. She could feel its radiation like a physical pressure, a slow, toxic drip into the room. A headache began to gnaw at her temples, a dull, thick ache that was utterly, terrifyingly human.
The bell finally rang, a sound of pure salvation. Students erupted into the chatter of release, snapping notebooks closed, sliding tablets into bags.
“Readings for next week are on the portal!” Kara called out, too brightly. “And no, the mid-term won’t just be on nucleosynthesis!”
Most of the stream flowed past her and out the door. Marcus, however, was taking his time. He picked up the green rock, turning it over in his hands, watching the internal light ebb and flow.Kara’s heart hammered against her ribs. She had to get it away from him.She had to get it contained. She casually walked up the aisle, pretending to collect a dropped pen.“Interesting specimen, Marcus,” she said, her tone lightly academic. “Geology field trip?”
He looked up, a defensive glint in his eye. “Found it.On the walkway by the east gate.Isn’t it wild? It’s warm.And it… hums.”
Yes.It hums. It’s humming my funeral dirge.
“It could be fluorite,” Kara said, leaning closer despite every instinct shrieking in protest.The nausea intensified.“Or maybe some kind of copper-bearing mineral. It might even be slightly radioactive. You really shouldn’t be handling it without proper…”
“It’s not radioactive,” Marcus interrupted, a smirk playing on his lips. “I checked with a Geiger counter from the lab.Nothing.It’s like it’s emitting light, but no other energy. That’s impossible, right?”
Not where I come from.
“Stranger things have happened,” Kara said, forcing a laugh.It sounded brittle. “Here, let me take it to the geology department.They can run a proper…”
She reached for it.
Marcus’s hand snapped back, clutching the rock to his chest.“No, that’s okay, Professor. I want to figure it out myself.I’ve got access to the spectrometry lab after hours. I’m going to run some tests tonight.”
Panic, cold and sharp, lanced through her. Tonight. If he cracked it open, if he vaporized even a fragment for spectrometry… the concentrated particles could aerosolize.They could fill the vent system. They could kill her in her office two floors above.“Marcus, that’s not advisable for an undergrad. The equipment is…”
“I know how to use it,” he said, his tone final.He slung his backpack on. “I’ll be careful. See you Thursday, Professor.”
He walked out, the rock a green heartbeat in his clenched fist.Kara stood frozen in the empty lecture hall. The holographic displays had shut down, leaving her in the sterile white light of overhead LEDs. The hidden Kryptonian power cell beneath the floor still hummed its steady, safe note. It was drowned out now by the phantom, poisonous whine of the rock, echoing in her mind.She needed that rock.
The apartment was dark when she landed silently on the balcony, the familiar soft whump of her boots on concrete a comfort. She phased through the locked door, the molecules of her suit and body shifting effortlessly for a second, and stepped into the living room.
The tension of the day—the constant, grinding fear that had sat like a stone in her gut since morning—morphed into a different kind of ache. She saw him reading on the couch, a single lamp painting his profile in warm gold, and the want was sudden, physical, and overwhelming. She needed to not be Supergirl, not Professor Danvers.She needed to feel something powerfully, wonderfully human.
“Hey,” she said, her voice rough.He looked up, a smile spreading.“Hey yourself. Tough day at the office?”
“You have no idea.”
She didn’t walk to him. She crossed the room in a blur of speed, the displaced air rustling the pages of his book. Before he could say another word, her mouth was on his, a hard, claiming kiss that was all hunger and desperation. She poured every ounce of her fractured day into it—the fear, the adrenaline, the clenching terror of that green glow.
He responded instantly, a low groan vibrating in his throat as his hands came up to cup her face.She tasted like night air and salt. She fumbled with the clasp of her cape, but her fingers, usually so precise, trembled.
“Let me,” he murmured against her lips, his own fingers deft and sure. The heavy fabric pooled on the floor with a soft shush. Her suit followed, the Kryptonian material parting willingly under his touch, until she stood there in just her briefs, the cool apartment air raising goosebumps on her skin that had withstood the vacuum of space.
He stood up, shedding his own clothes in a few economical movements. Then his hands were on her waist, lifting her as if she weighed nothing.She wrapped her legs around his hips, her core already aching, slick and ready. He carried her to the wall beside the balcony door, pinning her there with the solid heat of his body.
“Fuck, Kara,” he breathed, his lips traveling down her neck to the curve of her breast. His tongue flicked over her nipple, and she arched into him with a sharp gasp, the sensation so acute it was almost painful.
“Don’t be gentle,” she pleaded, her head thudding back against the wall. “I don’t want gentle tonight.”
He understood.He always did. One hand gripped her thigh, holding her open, while the other guided himself to her entrance. He looked into her eyes, his own dark with the same raw need, and pushed into her with one deep, relentless stroke.
She cried out, a ragged sound torn from her throat, as he filled her completely.There was no slow build, no tender rhythm. He set a punishing pace from the start, driving into her with a force that would have shattered any other woman, any other wall. Each thrust was a counterpoint to the dread that had gripped her all day, a physical rebellion against the invisible weakness seeping from a piece of her homeworld.
“Yes… god, right there,” she panted, her nails digging into the hard muscles of his shoulders. The friction was exquisite, a white-hot coil tightening deep in her belly. She met him thrust for thrust, her hips rolling, taking him deeper. The world narrowed to this: the slap of skin, his grunts in her ear, the smell of their sweat, the building, screaming pressure inside her.
She came violently, a cascade of sensations that ripped a scream from her lungs. Her body clamped around him, milking him, and with a final, deep drive, he followed her over the edge, his release hot inside her. They slumped against the wall, a tangled mess of limbs and labored breath.For a long moment, there was only silence, broken by their slowing heartbeats. The terrifying green glow was momentarily banished.
Then, gently, he eased her down, his arms moving to hold her instead of pin her. She rested her forehead against his chest, listening to the strong, steady human rhythm of his heart.“You wanna talk about it?” he whispered into her hair.
She shook her head.“Not yet.”
But she knew. As she stood there in the afterglow, the cool reality seeping back in, she knew. Marcus Chen was in a lab right now, with that rock.She had hours, maybe less, before he did something irreversible.
She pulled away, planting a soft, final kiss on his lips. “I have to go back out.”
He didn’t ask.He just nodded, his eyes full of a trust that felt like a weight. She dressed in a flash of superspeed—jeans, a dark hoodie, boots. Not the suit.Not for this.
From the balcony, National City spread out below, a galaxy of electric light. Somewhere in that grid, in the sterile glow of a university lab, a faint green pulse beat like a diseased heart. She took a breath, tasting the city’s air, searching for that specific, poisonous scent.She found it. A thread, faint but distinct, carried on the night breeze from the direction of campus.
Kara Danvers melted into the shadows, and Supergirl leapt into the dark.