Simon notices a forbidden door in the old school wing and, with Maja and Igor, steps into a locked classroom where something unsettling has been left behind.
At first glance, Primary School No. 12 looked exactly the same as it always had: grey corridors, cold tiles, the faint smell of polish and wet coats. But Simon had been noticing small changes ever since the start of eighth grade. Maybe it was Mr Rutkowski, their new tutor, who seemed to notice everything. Or maybe it was simply that Simon was no longer small enough to believe school was just a place you went to and left again.
On a dull Tuesday morning, with rain tapping hard against the windows, he arrived earlier than usual. He stopped by the library wall to wait for Maja and Igor and scrolled through an English app on his phone, half-reading, half-watching the hallway. That was when he heard it.
A door in the old wing gave a soft creak and swung open by itself.
Simon looked up.
He knew that part of the building. Or at least he knew about it. The headmaster had once mentioned it in one of those short, warning speeches adults gave when they wanted you to be curious about exactly the thing you were not supposed to touch. The old wing was closed for renovation and stayed shut. No one was allowed in. No exceptions.
Except the door was open now.
Simon lowered his phone and took a step closer. The corridor beyond was dim and narrow, lit by a strip of tired yellow bulbs. At the far end, a door with a metal number plate caught his eye.
305.
He leaned in through the crack and caught only a glimpse: dusty walls, a line of old lockers, and silence so deep it felt almost deliberate.
"What are you staring at?"
Maja had appeared beside him without a sound, her fringe damp from the rain and her notebook clutched in one hand.
Simon jerked back. "The door was open," he whispered. "I think someone went in there."
Maja narrowed her eyes and looked into the corridor herself. For once, she did not make a joke or ask ten questions at once. She simply stared at the open doorway, then at Simon.
"You’re serious."
"Very."
Before she could say more, Igor came jogging down the hall, backpack sliding off one shoulder, as if he had already missed half the morning and was too proud to care.
"What’s going on?"
Maja explained in a few quick sentences. Igor’s face lit up immediately, which was never a good sign.
"So we’re going in," he said.
"We are not," Maja said at once.
But she was already looking at the open door again.
Simon should have walked away. He knew that. Instead, he pushed the library wall, adjusted his grip on his phone, and followed them into the old wing.
The air changed at once. It was colder there, and heavier, as if the corridor had been sealed off from the rest of the school for years and was annoyed about being disturbed. Their footsteps sounded wrong, doubled and delayed, bouncing back from the walls a moment after they took them. Old desks stood stacked against one side, their metal legs bent, their tabletops filmed with dust. Faded posters about reading competitions and school plays hung crookedly as if no one had bothered to take them down before forgetting the room entirely.
Simon felt the back of his neck tighten.
Door 305 was at the end of the corridor. The padlock hung open.
"That’s not normal," Maja muttered.
Igor, of course, grinned as if that made it more interesting.
Simon reached for the handle and pushed.
The room was almost dark. A narrow blade of light from the corridor cut across the floor, revealing old desks, a blackboard, and a large cardboard box in the corner. Cobwebs hung from the top edge like torn thread. On the board, someone had drawn a pattern in chalk: sharp lines crossing in a shape too neat to be random, too messy to be a lesson.
Maja stepped closer to the blackboard. "Who would do that here?"
On the windowsill sat an open notebook, its pages curled and yellowed with age. The date on the cover made Simon freeze.
Ten years ago.
Igor reached for it.
Then the door slammed shut behind them with such force that all three of them jumped.
For a second, nobody moved.
In the sudden silence, something shifted in the room. Not a sound exactly. More like a breath being drawn where no one should have been standing.
Simon turned slowly toward the back of the classroom.
The dark corner by the box was no longer empty.