Ela crept through the garden overgrown with weeds. It was the middle of summer, the sun was seeping lazily through the leaves, and the old house at the end of the street looked even more deserted than usual. No one had lived here for years, so Ela knew it was the perfect place for a summer adventure. She was followed by Maks, her best friend, who had been saying for a few minutes now: - Is this really a good idea? But Ela just laughed and pulled him by the sleeve. Through the shattered door they went inside. The wooden floor creaked and the smell of dust and old books was in the air. Everything was covered in a thick layer of cobwebs. - See? There's no one here,' whispered Ela triumphantly. - 'Come on, let's go downstairs. They say you can find the strangest things in this cellar. They went down the narrow, creaking stairs, lighting their way with a torch, as the light from above had long since ceased to reach them. The cellar was cool and full of old, rusty objects: bicycles with broken wheels, trunks and crates full of unknown things. They walked past a large mirror, in which their silhouettes were reflected for a moment, when suddenly Ela heard a quiet crack. - 'Did you hear that? - Probably mice again - Maks shrugged his shoulders, although he wasn't so sure. In the corner of the cellar, behind a pile of old books, she spotted a door. It was not like any other - instead of normal wood, it shone, covered with a greenish glow, as if someone had drowned it in emerald. And, more strangely, it had no handle, and there were luminous streaks around the doorframe that swirled slowly, like mists at dawn. - 'I've never seen them here,' Ela whispered, feeling her heart beat faster. - 'Do you think someone lives behind them? Maks shook his head, but walked closer. He touched the door and it shook and made a deafening sound. At the same moment, the whirling of the lights accelerated and the air in the cellar became as if thicker. - Perhaps it was better not to... But Ela had already gently rested her hand on the emerald surface. The door swung noiselessly open, revealing an interior so bright that she had to shade her eyes. After a moment, her eyesight adjusted to the light and she saw... a completely different world - a forest of blue leaves, a sky on which two moons hung, and... something moving in the distance. Ela turned to Maks: - Come on, we have to check it out! They stood together at the threshold of the portal, hesitating for only a split second. As they set foot on the blue moss, the door behind them began to close slowly, and a quiet, disturbing sound came from the depths of the new world....