It all started one spring afternoon when Lena, Kuba and Maks were walking through the park in the small town of Glogowice. It was an ordinary day until Lena noticed that her shadow was moving differently from herself. She stopped and blinked - her shadow had just... scratched its head, although she hadn't! - Did you see that? - she whispered in surprise. The boys looked at her puzzled, but then Kuba willed a stone on the path to move without touching it - the stone suddenly rolled an inch away! Maks, wanting to prove that it was just a coincidence, looked at the bushes growing nearby and imagined one of them bending slightly. The bush actually moved, as if bowing to them. They quickly left the main path and sat down behind the swings. - Do we... do we have superpowers? - asked Lena quietly, looking around to see if anyone was eavesdropping on them. - 'I don't know,' added Kuba, 'but we need to check. Maybe someone else has them? That same evening they met in the old gazebo behind Lena's house. Each of them tried to use their new ability: Kuba could move small objects, Lena controlled her shadow and Maks influenced the movements of the plants. They decided to form the Invisible Heroes Club to train together and find out why something so unusual happened to them. Over the following days, they began to notice strange phenomena in the town: tree branches formed strange patterns, objects disappeared from the playground and flashes appeared in the sky, even when there was no storm. The most disturbing thing was what was happening at an old, abandoned factory on the outskirts of Glogowice. At night, green streaks of light emanated from its windows, and traces of small shoes could be seen among the grass growing against the wall. One evening, Lena pulled out a map of the town and pointed out the abandoned factory. - We have to go there. Something is going on there that is connected to our powers. Someone or something is watching us! At night, armed only with torches and baseball caps, they crept through a hole in the fence. Inside, it was semi-darkness and the floor bowed under their feet. Suddenly, a quiet creaking sounded and. right in front of them appeared a shadow that did not belong to either of them. This shadow began to grow, elongated, and then it spoke in a low, squeaky voice: - I have been waiting for you.... Invisible Heroes Club. The friends froze in stillness. Would their powers be enough to deal with what awaited in the old factory?