Burdock smelled of wet wood, heated dust and the lake. In the narrow streets, the wind chased away poplar feathers and small papers, and above the market square stood a clock tower so old that the edges of its bricks were smoothed by the mere glances of people. Lena had come here for a whole summer to visit her grandfather Felix, a clockmaker who lived right by the water, behind a thread and fastener shop. Grandpa's workshop was full of trinkets that had no right to fit in one room. Shelves strewn with caskets, open drawers with compartments as small as honeycomb cells, magnifying glasses and cogwheel dusting brushes. On the wall hung clocks: cuckoos, fans, pendulums. Some ticked loudly, others hardly at all. And all together they formed a background that sounded like rain in the leaves. "You'll see what it means to hear time". - said Grandpa Felix when Lena crossed the threshold. He had a silver beard, glasses like two drops of water and hands that could hold at once five screws so small they looked like pollen. Lena set her rucksack under the table and her gaze stopped on a pocket watch lying in an open biscuit tin. Its lid was plain, with no engraved initials. When Lena brushed her finger against it, the lid opened by itself. Inside, instead of a plain dial, someone had pasted a thin piece of paper. The tiny letters glittered as if they had been drawn with a needle in silver. "When at noon the shadow is lost, And the lake fog lifts, The thirteenth sound will run into the sky, Where no one is looking yet. Look for the key not in the casket, But where the breath leaves a trace. Don't turn away when you open it. Don't miss when time puts itself." Her grandfather looked over her shoulder and raised an eyebrow. "Oho. Someone here has interjected a piece of poetry into my gears. Probably one of the old customers." - He muttered, but Lena noticed that his fingers paused for a moment, as if he was listening not only to the ticking, but to something else. In the evening, the mist rose from the lake and began to crawl up the stairs under the windows, just as a cat can slip through an ajar door. Lena pressed her forehead against the cool glass. From outside, she could hear the splash of fish and the quiet cawing of crows from the main tower. She blew off steam on the glass and sketched a wave with her finger. Just as she was about to draw a sailboat, she saw something peculiar: the marks of her finger on the glass had survived, but right next to it, as if with a life of its own, a shape began to draw itself. First a thin line, then teeth, an arc, a hole. A drawing of a key blossomed on the glass, so precise that it was strange. Lena didn't breathe a moment. And then something tapped gently on the window sill. She looked down. There lay a small, cool object. She took it in her hand and sighed. It was a key - silvery, light and damp, as if taken straight out of the morning dew. "Grandfather!" - she called out, but at the same moment the outer clock on the tower rocked the air with an evening beat. One, two, three, four.... Lena began counting unconsciously. Ten, eleven, twelve. And then - a quiet, short sound after twelve, like a whisper. Thirteenth. As if someone was trying to blow into the cup from the inside. The next day Lena met Oskar. He lived two streets away and brought with him a scooter, a patch on his knee and a rucksack that smelled of ham and basil. "I'm Oskar. You must be Lena, the watchmaker's granddaughter, who knows how to stop the rain," he announced in all seriousness. "He doesn't stop the rain, he only fixes clocks," Lena replied, but smiled. Oskar had lake-coloured eyes and a tongue that liked to tell more than he knew. For two days they wandered around the market square, feeding the ducks and counting the notices of the players' performance scattered in places. Lena carried a fog key in her pocket, which warmed strangely in her hand as they passed the tower. Oskar claimed it was from emotion. "Clocks feel when you look at them". - he stated in a confident tone, then added in a whisper: "It was yesterday ... Did you hear that? That extra sound? Me too. Only everyone else seemed to be pretending not to." "I don't know if they were pretending," Lena said. - "Maybe it's not getting through to them." While the sun climbed across the sky, as if pouring down an invisible ladder, Lena and Oskar stood beneath the tower. A stone staircase led up to a heavy oak door, which was usually locked. On this day, however, someone had left them ajar. "Maybe it's Grandpa?" - wondered Lena. Oskar just nodded and pushed the door open with his hip. The interior smelled of metal oil, old wood and something cool, like the air over the water just before sunrise. As they climbed the spiral staircase, they could hear the hum of gears and the soft rumbling of large pendulums more and more clearly. Between the rungs of the ladder they could see pipes and beams on which two pigeons sat. One was missing a feather in its tail, but sat with the look of a bird that had seen more than one thing. Upstairs, a mechanism occupied the entire room. Golden circles with teeth as even as if drawn by the wind scribe himself moved in a rhythm that could be felt in the fingers. The sun's rays squeezed through the dial of the clock like a lace, drawing patches of light on the floor. Then Lena noticed a darker line in the wall, just behind the largest circle. As if someone had outlined a rectangle in the dust with their finger. She touched it. Under her fingers, the rough surface twitched and moved away a centimetre, then two. Hidden behind the mechanism was a narrow door - so narrow that it was adjacent to the beam almost without a gap. An old sign shone at eye level: "Don't turn around". A drop-shaped keyhole wove underneath. "Don't turn away? From what?" - Oskar ran his finger over the letters and quickly rubbed his hand over his T-shirt, as if he was afraid the writing would burn him. Lena felt the key in her pocket getting heavier. She took it out. In the light leaking through the dial, the key looked as if someone had blown it out of the morning mist and silvered it. When she brought it close to the lock, the metal clanked softly, with a high-pitched sound, like when a needle hits a record. At the same moment, the bells of noon began to toll in the town square, far below them. One. Two. Three. The springs in the tower mechanism vibrated. Four. Five. A slight chill ran through the walls. Six. Seven. Someone on the other side of the door played a short note on the flute - as thin as a ray. Eight. Nine. The door was still closed, but Lena sensed that something on the other side was waiting. Ten. Eleven. Oskar swallowed his saliva loudly. Twelve. Lena was almost out of breath. The dust swirled around them, as if moss had been blown off the beams. A dozen golden specks rose from the curtain of light on the floor, which for a moment resembled skylights. The mechanism, which had been moving confidently before, stopped for a blink of an eye and moved in the opposite direction, as if it had suddenly changed its mind. Lena realised that she was waiting for something exactly between twelve o'clock and something that should not happen. From the street, from the lake, came an unexpected gust - cool, reed-smelling. At the same moment there was a thirteenth sound. Not a loud one, but one that you could feel in your bones. The keyhole glowed with a thin rim. Lena lifted the key and its teeth matched the drop like note to note in a familiar tune. Just as she was about to slip it into the lock, something on the other side of the door knocked once, lightly, like a knuckle on the surface of the table. Then again, a little more boldly. From behind the boards a whispered name reached them, spoken as clearly as if someone were standing right next to them: "Leno..." Oskar grabbed her elbow. "Did you hear?" - he hissed. She heard. And beyond that light whisper the thin, addictive sound of the flute, which grew and growled as if calling. The key began to pulsate with warmth, and the letters "Don't turn away" trembled, as if the inscription was made of ice spiders. In the town square, someone burst out laughing, and somewhere on the lake a fish splashed. Lena tightened her fingers on the key. She took a deep breath, involuntarily looked over her shoulder at the clock face, where specks of light floated - and in that second she felt Oskar squeeze her sleeve tightly. "Don't look back." - he whispered. "Are you reading?" Another soft clatter from inside. This time it was accompanied by a trembling of the floor, as if something behind the door had shifted from foot to foot. Lena lifted the key higher until its teeth touched the edge of the hole. On the other side, the whispering stopped and a silence fell so thick that only their own hearts could be heard. Then, right next to her ear, from the side of the door, something else sounded - the short, accelerated breathing of someone who had been waiting for a long time. Lena slid the key into the lock and....