When we first heard Wandering Forest singing, no one believed us. Even Grandma, who always told the strangest stories, just smiled mysteriously and stroked the dog's paw. But me, Kuba, and my two best friends - Basia and Lena - knew that something unusual had happened. Our house was at the end of the village, right on the border with the forest, whose trees looked as if they were leaning over us, listening to our conversations. Everyone here told us not to go between the trunks after dark because you could get lost and never come back. But it was when the moon was shining brightest that we began to hear sounds - they were not the usual hooting of owls or rustling of hedgehogs. They resembled more distant melodies, quiet notes, as if someone was playing a harp hidden among the leaves. One evening, just after the sun had disappeared behind the hills, Lena came running to me, all breathless, holding an old key in her hand. - I found it on the path I used to walk with my grandfather! - she exclaimed, showing us the object. The key was no ordinary key - it had a spiral handle and an engraved leaf glittered on the head. - Do you think this means something? - Basia whispered with her eyes wide open. The next day we decided to find the place where the strange key fit. We took torches, sandwiches and.... of course a map we had been drawing for years, full of secret markings: "Here dwarves live", "Tree-shelter from the rain", "Spider clearing". The hike through the forest was different than usual. The air smelled sweet and the sounds became louder and louder. We came to a clearing full of yellow flowers that we had never seen here before. In the middle of it, just under a huge oak tree, was a metal casket locked with a leaf, exactly the same as the one on the key. My heart started pounding like a hammer. Basia held my hand, Lena with trembling fingers picked up the key and slipped it into the lock. As she began to turn it, there was a sound throughout the forest as if a thousand strings were playing at once. Skylights flew down from the trees and the air around us lit up with hundreds of coloured lights. Suddenly, the casket opened by itself....