Three friends uncover a hidden gateway beneath an ancient oak in Unai, where the night sky turns purple. When the opening begins to answer back, they realise the first step may not be theirs to choose.
For most of the year, Unai looked like any other town that had forgotten how to surprise anyone. Its streets ran straight, its windows glowed at predictable hours, and the old park at the edge of town was the sort of place people crossed without really seeing. But after dark, when the last trace of daylight thinned away, the sky over Unai deepened into a colour that did not belong to weather or season. It turned purple, faint at first, then richer, as if dusk had bruised the air.
Sara, Michal, and Lena had grown up under that sky. They knew its habits, its silences, the way fog collected in the mornings and clung to their shoes as they walked to lectures they never wanted to attend. In the evenings they met in the park, where the paths bent between dark hedges and the benches shone damp beneath the streetlamps. They had long ago learned to treat the town as something fixed. Nothing new happened in Unai. Nothing worth the trouble, anyway.
That changed the night Lena stopped beside the oldest oak in the park.
The tree had split and twisted with age until its roots rose from the ground like locked fingers. Kneeling in the wet grass, Lena frowned and brushed aside a mat of leaves. Something thin and silver had caught on the bark, half hidden in the roots, as if a strand of moonlight had been pulled loose and left behind. Sara leaned closer. The filament trembled when she touched it, sending a sharp tingling through her fingertips.
Michal let out a short laugh that sounded too loud in the quiet. “Either that’s some absurdly advanced wiring,” he said, “or we’ve stumbled onto a very bad idea.”
Lena did not laugh back. She was staring at the thread as it quivered beneath the bark. For a moment the air around the oak seemed to tighten, as if the tree had inhaled and was waiting to exhale.
They left before midnight, but none of them really slept. By the next evening they were back with torches, a charger for Michal’s phone, and the uneasy conviction that they were about to prove one of them right and all of them foolish.
The silver thread was still there.
It had spread through the roots like a vein of light, pulsing softly under the dark bark. The glow was not bright, only steady, but it made the shadows around the trunk look deeper than they should have been. Sara felt her pulse quicken as Lena crouched first, close enough to see her reflection in the pale shimmer.
Then Lena slid her hand between the roots.
She froze.
Sara took a step forward, but Lena was already drawing her hand back, her expression unreadable in the torchlight. Something small and cold flashed in her palm: an oval stone, smooth as river glass, dark at the centre and rimmed with a silver edge. When Michal reached for it, the instant his fingers touched the surface, the park filled with a low whisper, like wind moving through a place with no trees.
The torches flickered.
The ground under the oak gave a subtle shudder. Light spilled into the trunk where no gap had been a heartbeat before, and a narrow opening began to form beneath the roots, exhaling a strange air that smelled of rain, metal, and something older than all of them. Inside, colours moved where darkness should have been. Shapes shifted just beyond sight, too quick to name.
Then the whisper came again, closer this time, and it spoke in a voice that did not belong to any of them.
Sara turned sharply.
Behind them, in the black between the trees, a shadow had stepped out where no one should have been standing, and the opening under the oak widened as if it had been waiting for that sound all along.