The quiet buzzing of onboard systems echoed through the cramped interior of the Galactic Wanderer shuttle. Behind the panoramic windows, the wall of Jupiter's gas giant glowed ominously, and just below, yellow-orange sulphur formations covered the surface of Io - one of the solar system's most dangerous moons. The crew numbered four. Amira, the mission captain, had a unique sense of when something was going wrong. Zara, a computer scientist, was a master of code-breaking and robot design. Max, the astro-engineer, could fix literally anything, and Leo, the biologist, loved to look under every stone, searching for signs of life. On the eighteenth day of the expedition, as they orbited Io, an unfamiliar signal flashed on the communicator screen. It was a short-wave message: distorted sounds, repeating every few minutes, from a position corresponding to the old, abandoned research station "Prometheus". - 'According to the archives, the Prometheus was abandoned seven years ago after an unexplained accident,' said Amira, looking at the crew. - 'But if there is someone there? - Leo asked quietly. - 'Or something,' muttered Max. After a short deliberation, they decided to descend to the surface. Their shuttle slid through Io's thin atmosphere and landed on the outskirts of the station, surrounded by lava dust and yellow geysers of sulphur. Traversing the walkways in heavy spacesuits, the crew felt the atmosphere of a place that had not seen humans for years. In the station's main lobby, the air was heavy with silence. Everything seemed deserted - until Zara picked up a signal trail leading to an underground laboratory. The door was closed, a red light flashing on the console. - 'Someone is transmitting a signal right now...', Zara whispered, typing in the code. Max held his tools at the ready, Amira prepared the torch and Leo checked the motion detector. The door gave way, creaking ominously as it opened into a dark, icy corridor. At its end, a blue light flashed. The crew moved towards the mysterious light, and a sudden crackling sound came from the darkness....