When Kuba walked into class 2B at Antoni Gwoździec Secondary School, he felt as if the end of the world was about to come. It wasn't about a test, although you could count on that on a Wednesday morning, too. The reason was different - rumours circulating around the school about a new physics teacher, Professor Flejser. This guy suddenly appeared like unexpected hail at the school picnic: a long coat, shoes as if dug out of a time traveller's wardrobe and a haircut resembling a black tornado. Zośka was already sitting in her seat, browsing memes about failed experiments. - Do you think it's true that Flejser's former school doesn't exist in any records? - she whispered to Kuba as he took his seat next to her. - 'I heard he can build an engine out of a china box and two pencils,' chuckled Kuba ironically, eliciting a quiet giggle from Zośka. They didn't even manage to exchange half of the gossip, because he entered the classroom. First the smell of herbal hand cream rolled in, then checked trousers, and finally Professor Flejser - carrying under his arm something resembling a computer from the 1980s, laced with washing machine string. - Good morning, young people, welcome to the world of real science! - he called out and immediately plunged his hands into his backpack like a juggler preparing a trick. He pulled out... a rubber duck, a chrome spoon and a glass full of jelly beans. He threw it all into a glass ball of goldfish and set it on the lectern. - Today we will walk the fine line between genius and total failure! - he announced with the look on the face of the captain of the Titanic who has just spotted an iceberg but... decides to skate across it. It got quiet. Everyone held their breath, because no one wanted to be the first to be pointed out by the Professor for the experiment. Kuba felt his forehead sweat. Zośka pulled out a pen and the notebook opened by itself, perhaps in an act of desperation. Professor Flejser took the yellow duck in his hand, looked at it devoutly and then, smacking loudly, dropped it into the ball. He then stirred it all with a spoon, as if he was preparing the strangest dish in the history of TV cooking. - Who can tell me what happens when you add potential energy... and a pinch of imagination? - He asked, and his eyes shone uneasily. At that moment, a sudden sound came from the speaker in the ceiling: - Kuba Kwiatkowski and Sophie Mazur, please come to the secretariat! - It was strange, because neither of them had anything on their conscience. And yet the whole class looked at them as if they had just won a trip to another planet. As they left the classroom, Flejser looked behind them and threw a mysterious smile: - Watch out for the interdimensional passages in the corridor.... They walked down the creaking stairs, trying to understand why they had been summoned. As soon as they passed the school library, they heard an unusual metallic clatter from inside and someone whispering: "Password... give me the password!" Zośka looked at Kuba questioningly. The door to the dark room swung open in front of them. Inside, a cold blue light flicked and ridiculously deformed shadows danced across the walls. - Shall we go in? - whispered Zośka, feeling shivers run down her spine. Kuba took a deep breath. - I don't think we have a choice. You live once... They stood on the threshold of the library, not yet knowing that everything they thought about physics was about to be turned upside down....