On the outskirts of the Solar System, where ice mingles with vacuum, comet 9QX drifted. It was as huge as a city and for centuries was regarded as an empty lump. However, it was once chosen as the site of an experimental mining station. The project was abandoned - according to official reports - after strange failures and the disappearance of the crew. When Kyra gained access to the old transmission log, she already knew that this was not the end of 9QX's story. She was nineteen years old, studying cybernetics at an orbital university and loved breaking security protocols. Her best friend, Zaid, was fascinated by lost space installations and Lio, a pilot-adept, dreamed of flying where others would not dare to look. They met in the Zero-G café, right next to the docking station. Above their heads, swirling screens displayed advertisements for the latest neural implants and sports drones, but none of the three were paying attention. Kyra unfurled a hologram of a comet in front of them. "The signal from the Underworld came three days ago. Short, encrypted, evidently transmitted by hand. Someone is out there." Zaid stared at the pulsing lines of code. "According to the archives, no one has dared to return to 9QX for a decade. But if there really is someone left there..." "We need to fly there." Lio hated long deliberations. "I have access to an old courier ship. If we plan the route well, no one will notice us." They decided to act quickly - the sooner they took off, the less risk of someone pre-empting them. Preparations took all night. Kyra reprogrammed the ship's sensors to hide their presence from patrols. Zaid analysed the station plans, trying to find a safe route through the maze of mine tunnels. Lio practised manoeuvres in the simulator, as the comet had its own treacherous gravity field. Finally, after two days of flight, their ship anchored in the comet's frozen hangar. There was absolute silence all around, broken only by the sound of the correction engines running. Kyra read out the first data: "Oxygen is there, energy minimal. Ventilation systems are working - at least in theory." They entered through a tunnel suspended in the vacuum. The thick, black steel was covered in a strange tarnish, as if something had melted it and froze it again. Inside, it was twilight; the lights at the helmets cast shadows on the darkened walls. Lio led the way, Kyra monitored communications, Zaid secured the passageways. Deep down the corridor they found a severed communications cable and fresh footprints - someone had indeed been here. The further they descended, the thicker the atmosphere became. In one of the rooms they found a service robot who suddenly, on seeing them, raised his head. Its eyes flashed with a blue glow. A distorted human voice sounded in the loudspeaker: "You should not be here. Get back while you can." At the same instant, the entire corridor flashed with a pulsating light, and a steel wall spread between them and the exit. Outside, there was the sound of something heavy moving through the station. Then Kyra noticed on the holo-screen strange messages being transmitted from deep within the comet - something was trying to contact them, but the messages were distorted, as if someone or something was trying to relay a message from another level of reality. The three students froze - not knowing if the first step into the depths of comet 9QX was the beginning of a rescue mission or a dangerous game from which only a few return....