At a certain colourful school, in class one C, all the pupils were just opening their notebooks. Antek sat down in his favourite bench right by the window. Suddenly, right under his feet, there was a strange sound: 'tick-tock-tock'. Antek looked under the bench, but saw nothing there. - Did you hear that? - he asked Jagoda, who was sitting next to him, in a whisper. - What was that? Maybe it was a mouse! - whispered Jagoda with her eyes wide open. The sound repeated itself, even louder: "tick-tick-tick!" The whole class began to look around. Mrs Eve, their teacher, approached Antek: - What have you got under the bench there, children? But when she looked, the sound fell silent. The children started whispering and guessing what it could be. Could it be a magic watch? A mysterious school spirit? Or perhaps a hidden treasure? Suddenly the sound came again, this time coming from under the neighbouring bench! Antek, Jagoda and a few other pupils decided to quietly check where the mysterious "tick-tock-tock" was coming from....