Deep in the Old Forest, where the sun's rays danced among the leaves, lived a cheerful squirrel named Ola. Ola was very curious and loved to climb the highest branches to watch the world from above. One morning, while Ola was munching her favourite nut, a strange sound came to her ears: bam-bam-bam! Puzzled, she looked around, but saw no animals anywhere. So she decided to ask her friends for help. The first to appear was Susie the Owl, who was just returning from a night walk. Her big, round eyes got even bigger when Ola talked about the sound. "Maybe it's the wind?" wondered Susie. But just then the sound came again - this time even louder! Soon Ola and Zuzia were joined by Felka the Frog, who always had lots of ideas. "We need to collect more animals!" she called out. And so news of the mysterious sound swept through the forest. More and more curious animals gathered under the big oak tree in the clearing: Kazio the Hedgehog who rolled through the moss, Basia the Badger with her little brother and a whole family of mice. Everyone tried to guess what could make such amazing sounds. Some even started tapping with sticks to see if it sounded similar. Suddenly, a bam-bam-bam sounded right behind their backs. The animals froze in anticipation, wondering who or what was hiding behind the big bush....