At an altitude of fifty-five kilometres above the milky storm of Venus, the city of "Corona" clung to the sky like a jellyfish lit up by a light bulb. Giant support balloons, filled with helium and nitrogen, creaked deafeningly under the gusts. The sprinklers spat neutraliser and the ducts draining the acidic mist sounded like rain on a tin roof. Inside the gondola, in the cool twilight of the Institute of Wind and Light, Lila Kasperska sat in her headphones and watched the wind form sentences. Not in the poetic sense. Not this time. For three weeks, she searched for repetitive structures in the infrasound - tiny patterns in the jittery, oily hum of clouds. The graphs on the screens trembled, soft as frills. Only now the lines were no longer chaos. On the contrary: the residual echo from the Kalliope resonator, suspended at the edge of the outer 'Ariadne' platform, arranged the intervals into a rhythm. Too even to be mere coincidence. "Li-la." A whisper that was not a whisper at all, but a modulation with two consonants in floating density. On the screen the date: tomorrow. A phase shift, negative three seconds. No matter how she cursed the algorithms. It didn't matter how many times she zeroed the caches. The data was coming back. Smooth as a wave on the sand. - Again? - Anthony Bek asked, slipping his head through the door. He had his hair in a disobedient spring and a jacket trimmed with reflective tapes on which particles of neutraliser had left a dull, chalky mark. His hands smelled of grease and ozone. - Not again. Deeper. 'I've got negative latency and a string that looks like the name of your favourite filter,' Lila replied, gabbing at the interface. - Except that Kalliope hasn't sent packets on that frequency yet. According to the logs, she won't send them until the morning. From our tomorrow. Anthony stepped inside, leaning with his shoulder against the doorframe. - This is not a joke I like. Let's take it outside, on a clear channel. We'll go to the 'Ariadne', hook up a new resonator and see if the winds continue to play their tricks. Lila slipped off her headphones. Her throat was dry. The night over Venus was sometimes as bright as day - the clouds reflected the light of the city, warm and shadowless - but inside that glow lurked another darkness, calm and watchful. - 'The duty officer in Air Cartography said the "marginal" would hook us at dawn,' she muttered. - 'We'd better hurry before the front. The corridors of the 'Crown' smelled of metal and citrus detergent. Through the service window they could see the skinny ribs of the structure, the supports shone through a yellowish haze. As they walked, they passed panels of crumpled mesh on which dew had collected, bitter and aggressive, before neutralisers turned it into ordinary water. They walked in silence, each with their own thoughts about what they had seen and what they preferred not to see. In the outer airlock, Lila put on the suit with the skill the years had taught her: a sequence of buckles; a check of the seals; a test of the laryngeal overlay that modulated the voice so the breeze wouldn't rip off the words. Breath rumbled through the helmet like a drum. Through the visor, the world now seemed even closer, even intimate - as if one could touch the air and be touched in return. - 'I'll connect us on a local channel, no redirects through the core,' Anthony said, glancing at the airlock console. - 'Less interference, and if something goes wrong, at least we'll have our silence. - 'The silence on Venus is only in museums,' replied Lila with a forced smile. As the airlock doors opened onto the footbridge, they were struck by the gentle sway of the whole world. The outer platform of the 'Ariadne' stretched like a thin bridge over the wind. The grating beneath their feet trembled, but held, as it always did. On the left, the carrier balloon may have been in the air, its skin taut and dark. To the right, clouds were clouding below, frothy with an internal storm. Here and there something flashed - microslides of charge, spreading in pale blue streaks. - 'It looks calm,' assessed Anthony, although Lila could hear his modulated voice raising the ends of sentences a tad too high. - 'Two steps and we're at the side masthead. They walked slowly, hooking the carabiners to the lifeline, unhooking and hooking again. Slowly, rhythmically, like a dance. As Lila put her foot down, she could feel the tiny pulsing of the footbridge through her sole - not the trembling of the structure, but a deep tone she had known for years. The tone of this world. Kalliope's resonator stood affixed to the railing like a letterbox. Black, dull, with sensors fanning out. Lila opened the lid. Inside lay a memory module which, if the logs were to be believed, was only due to save the first packet of the new series tomorrow. She plugged in the new sensor, slender as a hand, and slowly slid the connector in. The screen inside the helmet lit up with the interface. The data flowed. - Did you get it? - Anthony asked. His silhouette leaned over the railing. From within the clouds came a sound that no one below would ever hear: a soft rumble, the singing of a great timpani. - I have. - Lila stared at the charts until her eyes baked. The intervals swam like fish in water. The pattern. The sequence. - Anthony... Before she could utter his name fully, the pattern folded into form. Two consonants. Her name, broken up but unmistakable. "Li-la." This time, however, the signal was not just a voice. It was a command, woven into a wave. A row of numbers lit up on the panel, right next to dozens of air parameters: -00:00:03.7 and dangled, as if someone was lapping it up. A negative progress clock. - Lila? - Anthony moved closer, putting his hand on the railing. - 'You've got a face like someone who's seen a winter heating bill. - He... - she broke off because she didn't know whether to say 'he', 'it' or 'wind'. - The signal comes before the broadcast. I'm listening for what hasn't had time to happen yet. There was a noise in the headphones. For a split second she stopped hearing her own breathing. Then the breathing returned, but with something underneath. Something that sounded like her own voice, only darker, transparent from too many years. Someone was talking, and the words were evenly spaced, like drops along gutters: "Lila, don't look left now." She blinked. She looked at Antek, who moved restlessly. - Can you hear? - She asked, because she needed this to be shared, human at the same time by both of them. - Just the wind and you. - Anthony shrugged his shoulders, but his hand squeezed the railing so hard it made the metal paint on his glove squeak. - "The marginal is shaking out faster than they predicted. I can feel it in the scaffolding. She glanced to the left after all. For half a second she saw something that had no right to exist: a smooth, geometric plane full of tiny protrusions, as if someone had hidden a huge comb of black glass in a cloud. It shimmered in the depths, superimposed like shadow upon shadow. Lila blinked rapidly and the image disintegrated into mere milk, crushed by the wind. "Too far," - said a voice in her ears, breathless and poised at once. - "Stay at the masthead. Count to three and move the resonator one segment to the right, not to the left. Don't confuse the sides." - Who is this? - growled Anthony, and in his modulation sounded an anxiety that Lila had not heard in him since they had rescued the undocked node after the last ice-crystal hail. - Who are you talking to? - To myself,' she whispered, and immediately regretted it, for how it sounded. - Or to whatever my voice sings on the way before I can hear it. The indicators began to float. The pressure jumped by a hair. The charges on the balloon hissed. Lila furrowed her brow as she felt someone else's step underfoot - no, not a step, after all, it was just the two of them. It was the footbridge, persuaded by the wind, playing a rhythm so similar to a human's that her spine remembered it like a familiar song. "Listen." The voice in the headphones now sounded direct, as if he was standing right next to him, elbow to elbow. "In three breaths something will grab the railing." - Something? - repeated Lila, wanting not to, and Anthony swallowed loudly. - "Something," repeated the voice, patient as a physics teacher. - "And it won't be the wind. Move the resonator now." Lila tightened her fingers on the Kalliope casing. The hinge squeaked in protest as she pulled the module back one segment. Two breaths - and at the same moment the wind, as if touched by a foreign hand, blocked her movement. Something rustled to her right, softly, like fabric sliding over fabric. Not a touch. The impact of a presence. - Lila! - Anthony wailed briefly as the metal beneath him trembled. From below, out of the dense light of the clouds, a shape he couldn't name slid out: an unform folding and unfolding at the edges of perception, as if someone were trying to lay a lump of dream on the tape of the world. A pinpoint corona of bluish heat slipped across a nearby support line and disappeared. The screen in Lila's helmet flicked on. The negative counter disappeared, only to return once more, as if in hesitation. "Don't turn your head." - said a voice, her voice, a shade older, stretched to a safe certainty. - "Don't look to the left. Don't look at what pretends to be a railing. If you take a step-"