Zosia was drawing a door with chalk on the still wet pavement. The rain had gone and the colours were stinging. She was eleven years old and had a head full of questions. Maks, the neighbour on the ground floor, was standing nearby counting bricks. - The door again? - He finally asked, although he already knew the answer. When Zosia closed the line, the chalk hissed like a spark. The cobblestones became smooth, as if someone had polished the old bricks. A door handle flashed in the middle, although no one had drawn it. A noise came from inside, reminiscent of the sea and pages being turned. Zosia touched the doorknob; it was cool and heavy as stone. Maks took a step back, but curiosity held him tight. - 'If something jumps out, we're running on three,' he warned. - And if it's just a story, we'll go in quietly - she replied. Zosia took a breath and pressed the handle lightly. The door swung open and a strip of light fell out from inside. Letters floated in the light, as if they had slipped out of a book. Wet footsteps appeared on the pavement, tiny and very fast. Someone on the other side coughed, and the handle moved of its own accord. The letters formed words, but disappeared before they could be read. A paper fish, twisted like origami, rolled out onto the threshold. With a flutter, it swam around their shoes and back into the glare. The courtyard tilted slightly, as if the world had taken a breath. - Can you hear it? - Maks whispered, as someone spoke their names. The door widened, made a chalky sound, and began to draw in air. Zosia grabbed the fence railing, and the handle vibrated again, from the inside.