First Published in The Literary Fantasy Magazine: Summer 2025. Reproduced below.
They lived beneath the oceans, at impossible, nightmare depths. As the millennia separated them from the races of man, they dove deeper and deeper, and in their underwater cities, the mer developed extraordinary societies of art, culture, and technological advancement.
They tapped into the nature of the blessed hydrogen molecule that had made all life on this planet possible. They forged power plants of immeasurable magnitude, pouring out hot fission energy. These enabled them to develop to their utmost pinnacle. They built branching highways of currents and electricity. They lit up the depths of the blackest ocean. They read the ancestry of the megalodons in the swirling sharks.
But for all this, they still did not see the danger boiling at the base of their cities, waiting to be unleashed in a series of poorly timed decisions on the part of Friyu Redclan, an operator at the Me’yun fission station, central Galpole, Western Anem.
The station sent heat and energy into five million homes and three million businesses, all collated under billions of conch-shell wire casings and tubes of clean gas, spinning and rotating back to the great ammonite shell housing the power plant.
Friyu punched the coolant tubes, letting the central chamber flood with ice-cold seawater. The resonator roiled and hissed, sending out hot vibrations through the air to fog up the twelve feet of solid glass that formed the barrier between the central burner and Friyu’s observation deck. The scalloped, clam-like encasement protected him, but if the reactor burned too hot, they risked a radiation leak. Too cold, and the engine might revert to a dull core. After that, it would take ages to get it burning and emitting normally.
But Galpole’s leaders would not accept such a lack of efficiency. Outages were punished; sometimes with trench duty, sometimes with public humiliation. If he let the site hiccup, even for a moment, Friyu risked exposing his clan name to these consequences. That, he could not accept.
He watched the gauges, indicated by globules floating between gradual measurements, and kept his eyes alert and bouncing between the tubes. He had done this every day for the last three years. The job had become so married to his consciousness, even his dreams brimmed with pipes, bubbles, and the rippling sound radiating off each of the core indicators. When he fell into it—really lost himself in the work—he was practically an extension of his instruments, the levers balancing easily in his deft, pale fingers.
But not when his supervisor, Frehr Rire, was around. In Rire’s presence, Friyu had a tendency to slip awkwardly at the lever. He had just done so and overcorrected, pushing the temperature gauge too far down. A blue undercurrent flooded the chamber above them. Friyu got it back up to a solid tread, and the color returned to a pulsing white-yellow. The electric air hummed pleasantly.
“You losing it, Redclan?” said Rire, his voice rolling hot off Friyu’s shoulders and back.
“No, sir. I am operating in flow. You startled me, is all.”
“And what about me should startle you?” Rire asked.
The mer’s luminescent yellow eyes constricted to tight pinpricks. Friyu felt a fresh wave of loathing for his boss.
“Nothing at all, sir,” he said.
“Because what’s startling are those trends in the thermal readouts,” said Rire. “Have you seen how high we’ve spiked over the last fourteen tides? It’ll look like we mean to insult the Hierarchies if something happens out here. A current gets irradiated, a minnow gets fried…. It’s on our gills, you get me?”
Friyu looked into the mer’s leering, beady-eyed face and nodded.
He found himself scanning every bubble in the readout, every holographic map of temperatures and flows. His fingers slid and bounced on the instruments on his shelf-rock dashboard. His people were not astronomers, but their logic deduced the nature of the celestial bodies all the same. He knew what power lay there, how it could warm and light and burn and mutilate and kill. He was well aware of the dangers.
So when the last module rose to a high red in its cylinder, Friyu Redclan flipped six of the fourteen stalks and twisted the ammonite spiral that composed the shutdown procedure.
And yet the procedure—designed to be infallible—failed.
The valves dispensed and brought a whole torrent of ice-cold seafloor water crashing down into the nuclear generator. Still, it burned so hot and so bright that it melted the shell of tempered glass between them, all twelve feet of it. Friyu was gone in seconds, but it would have pleased him to know that his supervisor followed shortly after.
The bulbous gases and toxic fumes rose in an enveloping cloud, eradicating all life within a 300-square-mile area of Galpole. Twenty million merfolk died instantly. The radiation made it all the way to the surface, where it triggered the military sirens of every major nation on every continent in the human world.
Above the surface, no one knew who had set off the bomb, only that it had to be a bomb.
Naturally, this meant that every nation had an impugnable casus belli. Someone was out there, carelessly flaunting nuclear weapons, and the funny thing about carelessness is that it tends to be contagious. Soon, everyone itched for the chance to get careless with a nuclear weapon.
The first bombs that fell on land did not target any major cities. Instead, they were intended to test the waters. Annapolis and Lviv went up, then Qods and Guadalajara. From there, the major population centers fell like dominoes.
Underwater, meanwhile, the radiation seeped in from every angle, currents mutated, burning, and sick. The remaining Anems went to war. Death reigned, and societal collapse mirrored the world above.
Together, the worlds of men and mer died, and neither kind ever knew a thing about the other.