At night, when most of the townspeople were asleep, red and white circus tents appeared in a deserted field. Lena and Cuba were the first to hear about it - they had their little hideout not far from where the Circus of Invisible Shadows had set up. Instead of wandering stalls and bustling commotion, the entrance was guarded by silent workers in owl masks. Mysterious posters were pasted on the poles: "A show for a select few only. Tonight, at midnight." Lena felt a thrill of excitement. Cuba, brave though he was, couldn't shake the feeling that there was more lurking in this circus than the displays of clowns and fire swallowers. After school, they watched as crates were brought into the tents, which no one opened. Occasionally they could hear strange sounds, neither laughing nor crying. They wondered if the shows were legal - even adults were not allowed behind the entrance curtains. Finally, they decided to go at night and see for themselves what was really going on. Under cover of darkness, they tore through the dense bushes and reached the back entrance. There was a smell of smoke and something else, unnamed: a sort of electricity floating in the air. Lena carefully lifted the fabric of the tent - they saw an arena illuminated by the glow of violet lamps, under which the shadows of the performers danced in the air, twisted into impossible shapes. The spectators whispered incantations under their breath, and the air around them vibrated. Suddenly the lights dimmed and one of the shadows broke away from its owner, looking straight at Lena and Kuba. In the blink of an eye, someone put a hand on their shoulder - was it a human or a shadow?