Joyful Adventure Primary School No. 13 has always been famous for two things: the weirdest school announcements and the latest model of jellybean machine. But no one expected that one afternoon in May, just after chemistry lessons, it would not be the rotten egg experiment that became the hero of the day. Filip, an expert at inventing embarrassing adventures, Ola, who was always the first to catch ironic jokes, and Bartek, the undisputed champion of the wet sponge throw, were accidentally drawn into the most unusual action in the school's history. It all started when Philip heard a strange rustling noise coming from the school cloakroom. Naturally, he couldn't help himself and convinced the others to check what was going on. The cloakroom was disturbingly empty, but a quiet mumbling could be heard behind the broom cupboard door, as if someone was reciting 'Pan Tadeusz' through a gas mask. Bartek, who claimed not to believe in ghosts, took out his phone and switched on his torch. Ola looked at Filip with a look on her face as if to say, "You've got us into quite a mess" - but she went first. The cupboard door creaked ominously and a mountain of... jelly beans fell out from inside. Lots of jelly beans. Raspberry ones, lemon ones, and even the odd one that resembled spinach-coloured glutes. From inside, however, emerged none other than Mr Roman, the school caretaker, covered in jelly beans and wearing a bizarre helmet made from energy drink cans. - Don't move! - he shouted, aiming at them with... with a giant battery-operated broom. - Only true friends survive the MEGA JELLY TEST of courage! Filip smiled broadly. Ola rolled her eyes. Bartek started recording everything with his mobile phone. Suddenly the lights in the cloakroom dimmed, the wardrobe slammed shut with a clatter and the floor began to shake. What were they supposed to do? Run away? Attack with jellybeans? Or... Solve Mr Roman's bizarre challenge? At that moment, the disturbingly familiar voice of the secretary rang out from the school speakers: - Attention, ten minutes until the end of break. Anyone who does not return to the lesson will meet the headmaster! And the wardrobe ... had just started to move spontaneously into the wall, taking them inside.