Three students staying late at Copernicus School find a hidden door beneath the lab and stumble onto a portal to another world, where one choice could change everything.
Copernicus School looked harmless in daylight. After sunset, it changed. The halls emptied, the fluorescent lights hummed overhead, and every sound Lena made felt too loud, like the building was listening.
She only wanted to grab the box of rocket-model parts from the basement and get out. The physics project was due in the morning, and the teacher had already gone home. Maks led the way with the torch on his phone, while Igor kept talking as if the dark was a dare he intended to win.
Lena hated the stairs down. The air below the lab was colder, damp with dust and old concrete. They had almost reached the storage cupboard when Maks stopped so suddenly that Lena nearly walked into him.
A thin ribbon of light cut across the floor behind the wardrobe.
Igor frowned. "That wasn't there before."
He shoved the cupboard aside. It scraped across the tiles with a metallic screech, revealing an iron door set into the wall. Strange symbols covered it in worn silver lines, neither letters nor numbers, but something in between. One mark looked almost like a formula Maks had once seen in a book about theoretical physics. The rest were nothing Lena could name.
Her stomach tightened. "What is that?"
Maks crouched, studying the symbols with the same expression he wore before solving a problem no one else could understand. "I don't know. But this isn't part of the school."
Igor reached for the handle anyway.
Lena grabbed his wrist, too late. The metal gave with a slow, heavy groan, and cold air spilled out from the crack as the door swung inward. Behind it lay a spiral staircase descending into darkness, the walls breathing a faint blue glow from somewhere far below. A low, restless sound drifted upward, like wind moving through a tunnel that had no end.
They went down because none of them could pretend they hadn't seen it.
At the bottom, the staircase opened into a room cut from raw concrete. In the centre of the floor, something shimmered above a dark ring of stone. It looked like a sheet of water stretched upright in the air, clear and trembling, reflecting not the basement ceiling but another sky entirely: violet clouds, three moons, and a horizon that did not belong to Earth.
Maks stared, white-faced. "A portal..."
Lena could only look. The surface pulsed softly, as if it had a heartbeat.
Igor took one step closer. "So what happens if we go through?"
Before anyone could answer, something moved in the shadows behind them.