In the small town on the edge of the forest, everyone talked about only one thing: the Big Blue Tent Circus had come to the Green Gables Park. Hania and her younger brother Staszek watched every day as the colourful carts set up in the clearing and the acrobats practised flips between the trees. On the day of the first show, Hania's whole school was boiling with excitement. No one had yet seen a circus where the lions had shiny blue feathers on their backs and the clowns could juggle flaming soap bubbles. As soon as dusk fell, the children rushed to the clearing. A basket of popcorn, candyfloss and two tickets were all they needed. Hania, dressed in a red cape, grabbed Staszek's hand and with a beating heart they crossed the entrance to the tent. Inside, the air smelled sweet and a little of magic. Jugglers appeared in the arena with cats at their side. Cats danced on their hind legs and clowns leapt over flaming hoops. But most impressive of all was Mr Lorenzo, a parrot trainer who spoke poems in French and sang in duet with frogs. During the break, Hania noticed something strange. Behind the velvet curtain, where no one was allowed to pass, a light flashed every now and then. Sometimes whispers and quiet laughter could be heard, as if someone was telling jokes to the three magpies. - Let's go over there and see! - whispered Staszek, hiding behind his sister's cloak. - Maybe it's the training of magicians or circus animals? They decided to sneak in during the next numbers. Between the arena and the mysterious curtain, the lights blinked more and more frequently. Suddenly they heard something that resembled thunder, although there was not a single cloud around. A shadow appeared from behind the curtain.... It looked like a figure wearing a huge, shining hat. In her hand she held a ball that glowed with a blue radiance. Hania froze. Staszek squeezed her hand so tightly that she felt a pinch. The figure came closer and looked them straight in the eye. In the arena, the crowd cheered, having no idea what was playing out right next to them. Would Hania and Staszek discover what was hiding behind the curtain? Or will they themselves become part of the most extraordinary number of the night?