The day at Middle School 17 was about to begin in a completely ordinary way – although some claimed that ordinariness was a myth at their school. Alan struggled to untangle the laces of his trainers, which had somehow become tied again during the night, and almost arrived late to Class 2C. Two people were already waiting for him at the spot: Karolina (known for the fact that the only way to make her laugh is to sneeze loudly into a banana) and Igor – a master at quickly memorising the composition of crisps. Today, however, there were no crisps, because from the morning onwards the whole school smelt of… broccoli. Or, more precisely, broccoli soup, which Mr Żukowski, the chemistry teacher and self-proclaimed culinary magician, decided to make as part of a lesson on ‘non-obvious reactions’. ‘Are you sure this is safe?’ whispered Karolina, as Igor approached her with the look of a man who knew that something strange was about to happen. ‘Last year he made lemonade that was still bubbling in the summer holidays,’ replied Alan, looking around the classroom suspiciously. Just then, the door opened with a loud slam, and Mr Żukowski walked in, wearing an apron from which stuck… a sprig of broccoli. In his hands he held a large pot from which greenish smoke was coming. ‘Good morning, welcome, young chemists!’ he called out enthusiastically. ‘Today we are going to perform an experiment that will change your view of vegetables!’ Alan exchanged communicative glances with Karolina and Igor. They knew that this was not going to be an ordinary lesson. Especially as Mr Żukowski set the pot in the middle of the classroom and then took a strange-looking pipette out of his pocket. ‘Each of you will have the opportunity to try… a magic potion!’ he announced proudly and scooped some soup into a test tube. At that moment, Igor, who had an exceptionally developed instinct for self-preservation, began to retreat quietly towards the door. However, before he could open it, all the windows and doors slammed automatically – as if someone, or something, did not want to let anyone out of the classroom. The green smoke began to thicken and the lights flickered. A sign appeared on the blackboard that no one had seen when they entered the classroom: ‘BROCCOLI TEST – FOR THE BRAVEST ONLY’. Mr Żukowski looked at the students with a broad smile. ‘Shall we begin?’ he asked, and a strange bubbling sound came from the pot, resembling… laughter?