In the Heart Forest, where the trees had leaves like hearts and butterflies flitted merrily from flower to flower, lived Frania and her best friend Leon. One morning, as the dew glistened on the grass, Frania found an old, colourful trunk under a big oak tree. The trunk had a golden lock in the shape of a smile. - Leon, come here! - cried Frania, and her voice echoed among the trees. Leon came running in breathlessly, and his brown eyes sparkled with curiosity. They carefully opened the trunk. Inside lay various objects: a soft cloud, a tiny mirror, a green feather and even a glass pebble that glowed blue. Frania touched the cloud - she immediately felt light and happy, as if she wanted to jump up from her seat! Leon took a feather - he felt a tickle in his tummy that reminded him of laughing with his friends. Each object had a different feeling in it: bold, cheerful or the kind that causes butterflies in the stomach. Suddenly... a soft, melodious sound came to them from deep in the forest, as if someone was playing bells. Frania and Leon looked at each other surprised and excited. - What could it be? - whispered Frania. They grabbed the trunk and set off along the path, with their hearts full of new feelings. With each step, the sound grew louder and louder, and the forest around them lit up with colourful skylights. In front of them grew a huge tree with a heart-shaped door. At the threshold of the tree they could see something they had never seen before....