At a strange school beside the park, the bell that marks break time vanishes. Zosia, Filip, Nina, and Tymon follow the clues into the cellar beneath the school.
At the end of Bird Street, beside the old park, stood a school called Under the Oak Leaf. Ivy climbed the brick walls, and in the middle of the playground grew a huge oak tree, thick as a watchtower and older than anyone could remember. That was where the trouble began for four friends: Zosia, Filip, Nina, and Tymon.
Zosia wore her hair in pigtails and filled her notebook with dragons of every shape and size. Filip knew strange facts about everything, from weather patterns to bats that slept upside down in the school cellar during winter. Nina preferred old books, quiet corners, and shelves that smelled of dust and paper. Tymon liked jokes, clever machines, and inventions that looked as if they ought to fall apart but somehow never did.
That morning, while the sky was still pale and the leaves on the ground shone with damp, a message raced through the school: the bell had gone missing.
It was not an ordinary bell. At Under the Oak Leaf, break time was announced by a recording of magpies laughing, one of Mr Lark’s inventions. He was the caretaker, repairman, and proud inventor of anything with wires, buttons, or wheels. Without the bell, the whole school seemed to lose its footing. A maths lesson wandered past lunchtime. In the library, the librarian read for so long that children started glancing at the windows, wondering if daylight itself had got lost.
When the four friends met beneath the oak tree, no one was quite sure whether it was break time or not. The playground buzzed with confused voices and teachers checking their watches as if the answers might appear there.
“This is mischief,” Tymon said at once, bouncing on his toes. “Proper mischief.”
“Or someone wanted the whole school confused,” Nina said, frowning.
Filip slipped a tiny magnifying glass from his pocket. “Then we should look for clues,” he said.
Zosia shut her notebook with a snap. “We start with the last person who saw the bell.”
That meant Mr Lark’s basement workshop, where he kept tools, spare parts, and every strange invention the school had ever needed. The stairs down were narrow and cold, and the corridor beneath the school smelled of old stone and machine oil. Doors creaked in the dark. A map of the school fluttered on the wall as they passed, though there was no wind.
At the bottom step, a light blinked once in the gloom.
Then, from behind one of the workshop doors, came a soft metallic clatter and a laugh that was too low, too rough, and far too close to be magpies.