Mystery under the Big Tent

Ela and Kuba loved adventure, so when the famous Luna circus came to town, they couldn't wait for the show. The huge, colourful tent in the park looked like an enchanted mountain, and the smell of candyfloss and popcorn was in the air. Inside, artists on stilts circulated, sparkling horses danced around the arena and in the corner sat an aged clown called Barnabas, who could conjure up a balloon dog with his eyes closed. Kids sat right by the railing, ready to stretch their necks like ostriches to see every trick and trick. But the most excitement came from the announcer's mysterious announcement: - Dear spectators! Today, just once, just with us: The Invisible Trick Show! Whoever solves its secret will become an honoured guest of the circus! As the lights went out and quiet music came from the speakers, Ela noticed a strange, pulsating light under the arena. She poked Kuba with her elbow. Was it a special effect? Kuba, always curious, whispered: - Let's go see what's going on there! Maybe it's part of that invisible trick! After the show was over, they slipped out of their aunt's care and snuck backstage with all their might. Among the barrels of confetti and cages of talking parrots, they found a secret door leading under the arena. Behind them there was semi-darkness, but the light that Ela could see pulsed ever stronger. They could see glistening reflections on the walls and shadows of irregular shapes. Suddenly they heard a quiet whisper: - Who came here? You are not allowed to be here! Ela and Kuba froze, feeling a growing excitement and fear. Someone was in the basement of the circus! Or was it the one guarding the secret of the Invisible Trick? A figure appeared at the end of the corridor.... and then...